The Stream and its subclasses, a subclass of the Music21Object, is the fundamental container of offset-positioned notation and musical elements in music21. Common Stream subclasses, such as the Measure and Score objects, are defined in this module.
Inherits from: Music21Object, JSONSerializer
This is the fundamental container for Music21Objects; objects may be ordered and/or placed in time based on offsets from the start of this container.
As a subclass of Music21Object, Streams have offsets, priority, id, and groups.
Streams may be embedded within other Streams. As each Stream can have its own offset, when Streams are embedded the offset of an element is relatively only to its parent Stream. The flat property provides access to a flat representation of all embedded Streams, with offsets relative to the top-level Stream.
The Stream elements attribute provides the contents of the Stream as a list. Direct access to, and manipulation of, the elements list is not recommended. Instead, use the host of high-level methods available.
The Stream, like all Music21Objects, has a music21.duration.Duration that is usually the “release” time of the chronologically last element in the Stream (that is, the highest onset plus the duration of any element in the Stream). The duration, however, can be “unlinked” and explicitly set independent of the Stream’s contents.
The first element passed to the Stream is an optional list, tuple, or other Stream of music21 objects which is used to populate the Stream by inserting each object at its offset property. Other arguments and keywords are ignored, but are allowed so that subclassing the Stream is easier.
>>> from music21 import *
>>> s1 = stream.Stream()
>>> s1.append(note.HalfNote('C#4'))
>>> s1.append(note.QuarterNote('D5'))
>>> s1.duration.quarterLength
3.0
>>> for thisNote in s1.notes:
... print thisNote.octave
4
5
This is a demonstration of creating a Stream with other elements, including embedded Streams (in this case, music21.stream.Part, a Stream subclass):
>>> c1 = clef.TrebleClef()
>>> c1.offset = 0.0
>>> n1 = note.EighthNote("E-6")
>>> n1.offset = 1.0
>>> p1 = stream.Part()
>>> p1.offset = 0.0
>>> p1.id = 'embeddedPart'
>>> p1.append(note.Rest()) # quarter rest
>>> s2 = stream.Stream([c1, n1, p1])
>>> s2.duration.quarterLength
1.5
>>> s2.show('text')
{0.0} <music21.clef.TrebleClef>
{0.0} <music21.stream.Part embeddedPart>
{0.0} <music21.note.Rest rest>
{1.0} <music21.note.Note E->
Stream attributes
- isFlat¶
Boolean describing whether this Stream contains embedded sub-Streams or Stream subclasses (not flat).
- autoSort¶
Boolean describing whether the Stream is automatically sorted by offset whenever necessary.
- isSorted¶
Boolean describing whether the Stream is sorted or not.
- flattenedRepresentationOf¶
When this flat Stream is derived from another non-flat stream, a reference to the source Stream is stored here.
Attributes without Documentation: isMeasure, isStream
Attributes inherited from Music21Object: classSortOrder, isSpanner, isVariant, id, groups, hideObjectOnPrint
Stream properties
- notes¶
The notes property of a Stream returns a new Stream object that consists only of the notes (including Note, Chord, etc.) found in the stream. This excludes Rest objects.
In versions of music21 before alpha 6, the “notes” property also returned rests. Thus you may find some old programs that use “notes” and expect to find rests. These programs should be converted to use notesAndRests
>>> from music21 import * >>> s1 = stream.Stream() >>> k1 = key.KeySignature(0) # key of C >>> n1 = note.Note('B') >>> r1 = note.Rest() >>> c1 = chord.Chord(['A', 'B-']) >>> s1.append([k1, n1, r1, c1]) >>> s1.show('text') {0.0} <music21.key.KeySignature of no sharps or flats> {0.0} <music21.note.Note B> {1.0} <music21.note.Rest rest> {2.0} <music21.chord.Chord A B-> >>> s1.notes.show('text') {0.0} <music21.note.Note B> {2.0} <music21.chord.Chord A B->
- pitches¶
Returns all Pitch objects found in any element in the Stream as a Python List. Elements such as Streams, and Chords will have their Pitch objects accumulated as well. For that reason, a flat representation is not required.
Pitch objects are returned in a List, not a Stream. This usage differs from the .notes property, but makes sense since Pitch objects usually have by default a Duration of zero. This is an important difference between them and music21.note.Note objects.
>>> from music21 import corpus >>> a = corpus.parse('bach/bwv324.xml') >>> partOnePitches = a.parts[0].pitches >>> len(partOnePitches) 25 >>> partOnePitches[0:10] [B4, D5, B4, B4, B4, B4, C5, B4, A4, A4]Note that the pitches returned above are objects, not text:
>>> partOnePitches[0].octave 4Since pitches are found from within internal objects, flattening the stream is not required:
>>> len(a.pitches) 104Pitch objects are also retrieved when stored directly on a Stream.
>>> from music21 import * >>> pitch1 = pitch.Pitch() >>> st1 = stream.Stream() >>> st1.append(pitch1) >>> foundPitches = st1.pitches >>> len(foundPitches) 1 >>> foundPitches[0] is pitch1 TrueChords get their pitches found as well:
>>> c = chord.Chord(['C4','E4','G4']) >>> n = note.Note('F#4') >>> m = stream.Measure() >>> m.append(n) >>> m.append(c) >>> m.pitches [F#4, C4, E4, G4]
- atSoundingPitch¶
Get or set the atSoundingPith status. Valid values are True, False, and ‘unknown’.
>>> from music21 import * >>> s = stream.Stream() >>> s.atSoundingPitch = True >>> s.atSoundingPitch = False >>> s.atSoundingPitch = 'unknown' >>> s.atSoundingPitch 'unknown' >>> s.atSoundingPitch = 'junk' Traceback (most recent call last): StreamException: not a valid at sounding pitch value: junk
- beat¶
No documentation.
- beatDuration¶
unlike other Music21Objects, streams always have beatDuration of None
- beatStr¶
unlike other Music21Objects, streams always have beatStr (beat string) of None
- beatStrength¶
unlike other Music21Objects, streams always have beatStrength of None
- derivationChain¶
Return a list Streams that this Stream was derved from. This provides a way to obtain all Streams that this element passed through, such as those created by getElementsByClass() or flat.
>>> from music21 import * >>> s1 = stream.Stream() >>> s1.repeatAppend(note.Note(), 10) >>> s1.repeatAppend(note.Rest(), 10) >>> s2 = s1.getElementsByClass('GeneralNote') >>> s3 = s2.getElementsByClass('Note') >>> s3.derivationChain == [s2, s1] True
- derivationMethod¶
Returns or sets a string representing how this stream was derived from another Stream.
There are currently no limitations on this string. This might change.
For instance:
>>> from music21 import * >>> s1 = converter.parse("C2 D2", "2/4") >>> s1m = s1.makeMeasures() >>> s1m1 = s1m.measure(1) >>> s1m1.derivesFrom is s1m True >>> s1m1.derivationMethod 'measure' >>> s1m1.derivationMethod = 'getElementsByClass' >>> s1m1.derivationMethod 'getElementsByClass'
- derivesFrom¶
Return a reference to the Stream that created this Stream, if such a Stream exists.
See Derivation for more information.
>>> from music21 import * >>> s1 = stream.Stream() >>> s1.repeatAppend(note.Note(), 10) >>> s1.repeatAppend(note.Rest(), 10) >>> s2 = s1.getElementsByClass('Note') >>> s2.derivesFrom == s1 True
- duration¶
Returns the total duration of the Stream, from the beginning of the stream until the end of the final element. May be set independently by supplying a Duration object.
>>> from music21 import * >>> a = stream.Stream() >>> q = note.QuarterNote() >>> a.repeatInsert(q, [0,1,2,3]) >>> a.highestOffset 3.0 >>> a.highestTime 4.0 >>> a.duration.quarterLength 4.0Advanced usage: override the duration from what is set:
>>> newDuration = duration.Duration("half") >>> newDuration.quarterLength 2.0 >>> a.duration = newDuration >>> a.duration.quarterLength 2.0Note that the highestTime for the stream is the same whether duration is overriden or not:
>>> a.highestTime 4.0
- elements¶
A list representing the elements contained in the Stream.
Directly getting, setting, and manipulating this list is reserved for advanced usage. Instead, use the the provided high-level methods. When setting .elements, a list of Music21Objects can be provided, or a complete Stream. If a complete Stream is provided, elements are extracted from that Stream. This has the advantage of transferring offset correctly and geting _endElements.
>>> from music21 import * >>> a = stream.Stream() >>> a.repeatInsert(note.Note("C"), range(10)) >>> b = stream.Stream() >>> b.repeatInsert(note.Note("C"), range(10)) >>> b.offset = 6 >>> c = stream.Stream() >>> c.repeatInsert(note.Note("C"), range(10)) >>> c.offset = 12 >>> b.insert(c) >>> b.isFlat False >>> a.isFlat True >>> a.elements = b # assigning from a Stream >>> a.isFlat False >>> len(a.flat.notes) == len(b.flat.notes) == 20 True
- finalBarline¶
Get or set the final barline of this Stream’s Measures, if and only if there are Measures defined as elements in this Stream. This method will not create Measures if non exist. Setting a final barline to a Stream that does not have Measure will raise an exception.
This property also works on Scores that contain one or more Parts. In that case a lost of barlines can be used to set the final barline.
>>> from music21 import * >>> s = corpus.parse('bwv66.6') >>> s.finalBarline = 'none' >>> s.finalBarline [<music21.bar.Barline style=none>, <music21.bar.Barline style=none>, <music21.bar.Barline style=none>, <music21.bar.Barline style=none>]
- flat¶
A very important read-only property that returns a new Stream that has all sub-containers “flattened” within it, that is, it returns a new Stream where no elements nest within other elements.
Here is a simple example of the usefulness of .flat. We will create a Score with two Parts in it, each with two Notes:
>>> from music21 import * >>> sc = stream.Score() >>> p1 = stream.Part() >>> p1.id = 'part1' >>> n1 = note.Note('C4') >>> n2 = note.Note('D4') >>> p1.append(n1) >>> p1.append(n2)>>> p2 = stream.Part() >>> p2.id = 'part2' >>> n3 = note.Note('E4') >>> n4 = note.Note('F4') >>> p2.append(n3) >>> p2.append(n4) >>> sc.insert(0, p1) >>> sc.insert(0, p2)When we look at sc, we will see only the two parts:
>>> sc.elements [<music21.stream.Part part1>, <music21.stream.Part part2>]we can get at the notes by using the indices of the stream to get the parts and then looking at the .elements there:
>>> sc[0].elements [<music21.note.Note C>, <music21.note.Note D>] >>> sc.getElementById('part2').elements [<music21.note.Note E>, <music21.note.Note F>]but if we want to get all the notes, the easiest way is via calling .flat on sc and looking at the elements there:
>>> sc.flat.elements [<music21.note.Note C>, <music21.note.Note E>, <music21.note.Note D>, <music21.note.Note F>]Flattening a stream is a great way to get at all the notes in a larger piece. For instance if we load a four-part Bach chorale into music21 from the integrated corpus, it will appear at first that there are no notes in the piece:
>>> bwv66 = corpus.parse('bach/bwv66.6') >>> len(bwv66.notes) 0This is because all the notes in the piece lie within music21.stream.Measure objects and those measures lie within music21.stream.Part objects. It’d be a pain to navigate all the way through all those objects just to count notes. Fortunately we can get a Stream of all the notes in the piece with .flat.notes and then use the length of that Stream to count notes:
>>> bwv66flat = bwv66.flat >>> len(bwv66flat.notes) 165If you look back to our simple example of four notes above, you can see that the E (the first note in part2) comes before the D (the second note of part1). This is because the flat stream is automatically sorted like all streams are by default. The next example shows how to change this behavior.
>>> s = stream.Stream() >>> s.autoSort = False >>> s.repeatInsert(note.Note("C#"), [0, 2, 4]) >>> s.repeatInsert(note.Note("D-"), [1, 3, 5]) >>> s.isSorted False >>> g = "" >>> for myElement in s: ... g += "%s: %s; " % (myElement.offset, myElement.name) >>> g '0.0: C#; 2.0: C#; 4.0: C#; 1.0: D-; 3.0: D-; 5.0: D-; ' >>> y = s.sorted >>> y.isSorted True >>> g = "" >>> for myElement in y: ... g += "%s: %s; " % (myElement.offset, myElement.name) >>> g '0.0: C#; 1.0: D-; 2.0: C#; 3.0: D-; 4.0: C#; 5.0: D-; ' >>> q = stream.Stream() >>> for i in range(5): ... p = stream.Stream() ... p.repeatInsert(music21.Music21Object(), range(5)) ... q.insert(i * 10, p) >>> len(q) 5 >>> qf = q.flat >>> len(qf) 25 >>> qf[24].offset 44.0
- highestOffset¶
Get start time of element with the highest offset in the Stream. Note the difference between this property and highestTime which gets the end time of the highestOffset
>>> from music21 import * >>> stream1 = stream.Stream() >>> for offset in [0, 4, 8]: ... n = note.WholeNote('G#') ... stream1.insert(offset, n) >>> stream1.highestOffset 8.0 >>> stream1.highestTime 12.0
- highestTime¶
Returns the maximum of all Element offsets plus their Duration in quarter lengths. This value usually represents the last “release” in the Stream.
Stream.duration is usually equal to the highestTime expressed as a Duration object, but it can be set separately for advanced operations.
Example: Insert a dotted half note at position 0 and see where it cuts off:
>>> from music21 import * >>> p1 = stream.Stream() >>> p1.highestTime 0.0 >>> n = note.Note('A-') >>> n.quarterLength = 3 >>> p1.insert(0, n) >>> p1.highestTime 3.0Now insert in the same stream, the dotted half note at positions 1, 2, 3, 4 and see when the final note cuts off:
>>> p1.repeatInsert(n, [1, 2, 3, 4]) >>> p1.highestTime 7.0
- isGapless¶
No documentation.
- lowestOffset¶
Get the start time of the Element with the lowest offset in the Stream.
>>> from music21 import * >>> stream1 = stream.Stream() >>> for x in range(3,5): ... n = note.Note('G#') ... stream1.insert(x, n) ... >>> stream1.lowestOffset 3.0If the Stream is empty, then the lowest offset is 0.0:
>>> stream2 = stream.Stream() >>> stream2.lowestOffset 0.0
- metadata¶
Get or set the Metadata object found at the beginning (offset 0) of this Stream.
>>> from music21 import * >>> s = stream.Stream() >>> s.metadata = metadata.Metadata() >>> s.metadata.composer = 'frank' >>> s.metadata.composer 'frank'
- midiFile¶
Get or set a music21.midi.base.MidiFile object.
- musicxml¶
Return a complete MusicXML reprsentation as a string.
- mx¶
Create and return a musicxml Score object.
>>> from music21 import * >>> n1 = note.Note() >>> measure1 = stream.Measure() >>> measure1.insert(n1) >>> str1 = stream.Stream() >>> str1.insert(measure1) >>> mxScore = str1.mx
- notesAndRests¶
The notesAndRests property of a Stream returns a new Stream object that consists only of the notes and rests (including Note, Chord, Rest, etc.) found in the stream.
In versions of music21 before alpha 6, the “notes” property also returned rests. Thus you may find some old programs that use “notes” and expect to find rests. These programs should be converted to use notesAndRests
>>> from music21 import * >>> s1 = stream.Stream() >>> k1 = key.KeySignature(0) # key of C >>> n1 = note.Note('B') >>> c1 = chord.Chord(['A', 'B-']) >>> s1.append([k1, n1, c1]) >>> s1.show('text') {0.0} <music21.key.KeySignature of no sharps or flats> {0.0} <music21.note.Note B> {1.0} <music21.chord.Chord A B-> >>> notes1 = s1.notesAndRests >>> notes1.show('text') {0.0} <music21.note.Note B> {1.0} <music21.chord.Chord A B->
- offsetMap¶
Returns a list where each element is a dictionary consisting of the ‘offset’ of each element in a stream, the ‘endTime’ (that is, the offset plus the duration) and the ‘element’ itself. Also contains a ‘voiceIndex’ entry which contains the voice number of the element, or None if there are no voices.
>>> from music21 import * >>> n1 = note.QuarterNote() >>> c1 = clef.AltoClef() >>> n2 = note.HalfNote() >>> s1 = stream.Stream() >>> s1.append([n1, c1, n2]) >>> om = s1.offsetMap >>> om[2]['offset'] 1.0 >>> om[2]['endTime'] 3.0 >>> om[2]['element'] is n2 True >>> om[2]['voiceIndex']
- rootDerivation¶
Return a reference to the oldest source of this Stream; that is, chain calls to derivesFrom until we get to a Stream that cannot be further derived.
>>> from music21 import * >>> s1 = stream.Stream() >>> s1.repeatAppend(note.Note(), 10) >>> s1.repeatAppend(note.Rest(), 10) >>> s2 = s1.getElementsByClass('Note') >>> s2.derivesFrom == s1 True
- seconds¶
Get or set the the duration of this Stream in seconds, assuming that this object contains a MetronomeMark or MetricModulation.
>>> from music21 import * >>> s = corpus.parse('bwv66.6') # piece without a tempo >>> sFlat = s.flat >>> sFlat.insert(0, tempo.MetronomeMark('adagio')) >>> sFlat.seconds 38.57142857...
- secondsMap¶
Returns a list where each element is a dictionary consisting of the ‘offsetSeconds’ in seconds of each element in a Stream, the ‘duration’ in seconds, the ‘endTimeSeconds’ in seconds (that is, the offset plus the duration), and the ‘element’ itself. Also contains a ‘voiceIndex’ entry which contains the voice number of the element, or None if there are no voices.
>>> from music21 import * >>> mm1 = tempo.MetronomeMark(number=120) >>> n1 = note.QuarterNote() >>> c1 = clef.AltoClef() >>> n2 = note.HalfNote() >>> s1 = stream.Stream() >>> s1.append([mm1, n1, c1, n2]) >>> om = s1.secondsMap >>> om[3]['offsetSeconds'] 0.5 >>> om[3]['endTimeSeconds'] 1.5 >>> om[3]['element'] is n2 True >>> om[3]['voiceIndex']
- semiFlat¶
Returns a flat-like Stream representation. Stream sub-classed containers, such as Measure or Part, are retained in the output Stream, but positioned at their relative offset.
>>> from music21 import * >>> s = stream.Stream() >>> p1 = stream.Part() >>> p1.id = 'part1' >>> n1 = note.Note('C5') >>> p1.append(n1)>>> p2 = stream.Part() >>> p2.id = 'part2' >>> n2 = note.Note('D5') >>> p2.append(n2) >>> s.insert(0, p1) >>> s.insert(0, p2) >>> sf = s.semiFlat >>> sf.elements [<music21.stream.Part part1>, <music21.note.Note C>, <music21.stream.Part part2>, <music21.note.Note D>] >>> sf[0] <music21.stream.Part part1> >>> sf[1] <music21.note.Note C> >>> sf[0][0] <music21.note.Note C>
- sorted¶
Returns a new Stream where all the elements are sorted according to offset time, then priority, then classSortOrder (so that, for instance, a Clef at offset 0 appears before a Note at offset 0)
if this Stream is not flat, then only the highest elements are sorted. To sort all, run myStream.flat.sorted
For instance, here is an unsorted Stream
>>> from music21 import * >>> s = stream.Stream() >>> s.autoSort = False # if true, sorting is automatic >>> s.insert(1, note.Note("D")) >>> s.insert(0, note.Note("C")) >>> s.show('text') {1.0} <music21.note.Note D> {0.0} <music21.note.Note C>But a sorted version of the Stream puts the C first:
>>> s.sorted.show('text') {0.0} <music21.note.Note C> {1.0} <music21.note.Note D>While the original stream remains unsorted:
>>> s.show('text') {1.0} <music21.note.Note D> {0.0} <music21.note.Note C>
- spannerBundle¶
A high-level object for Spanner management. This is only a gettable property.
- spanners¶
Return all Spanner objects (things such as Slurs, long trills, or anything that connects many objects) into a Stream or Stream subclass.
>>> from music21 import * >>> s = stream.Stream() >>> s.insert(0, spanner.Slur()) >>> s.insert(0, spanner.Slur()) >>> len(s.spanners) 2
- variants¶
Return a Stream containing all Variant objects in this Stream.
>>> from music21 import * >>> s = stream.Stream() >>> s.repeatAppend(note.Note(), 8) >>> v1 = variant.Variant([note.Note('D#4'), note.Note('F#4')]) >>> s.insert(3, v1) >>> [p for p in s.pitches] [C4, C4, C4, C4, C4, C4, C4, C4] >>> len(s.variants[0]) 2
- voices¶
Return all Voices objects in a Stream or Stream subclass.
>>> from music21 import * >>> s = stream.Stream() >>> s.insert(0, stream.Voice()) >>> s.insert(0, stream.Voice()) >>> len(s.voices) 2Properties inherited from Music21Object: activeSite, classes, derivationHierarchy, isGrace, measureNumber, offset, priority
Properties inherited from JSONSerializer: json
Stream methods
- append(others)¶
Add a Music21Object (including another Stream) to the end of the current Stream.
If given a list, will append each element in order after the previous one.
The “end” of the stream is determined by the highestTime property (that is the latest “release” of an object, or directly after the last element ends).
runs fast for multiple addition and will preserve isSorted if True
>>> from music21 import * >>> a = stream.Stream() >>> notes = [] >>> for x in range(0,3): ... n = note.Note('G#') ... n.duration.quarterLength = 3 ... notes.append(n) >>> a.append(notes[0]) >>> a.highestOffset, a.highestTime (0.0, 3.0) >>> a.append(notes[1]) >>> a.highestOffset, a.highestTime (3.0, 6.0) >>> a.append(notes[2]) >>> a.highestOffset, a.highestTime (6.0, 9.0) >>> notes2 = []since notes are not embedded in Elements here, their offset changes when they are added to a stream!
>>> for x in range(0,3): ... n = note.Note("A-") ... n.duration.quarterLength = 3 ... n.offset = 0 ... notes2.append(n) >>> a.append(notes2) # add em all again >>> a.highestOffset, a.highestTime (15.0, 18.0) >>> a.isSequence() TrueAdding a note that already has an offset set does nothing different from above! That is, it is still added to the end of the Stream:
>>> n3 = note.Note("B-") >>> n3.offset = 1 >>> n3.duration.quarterLength = 3 >>> a.append(n3) >>> a.highestOffset, a.highestTime (18.0, 21.0) >>> n3.getOffsetBySite(a) 18.0
- insert(offsetOrItemOrList, itemOrNone=None, ignoreSort=False, setActiveSite=True)¶
Inserts an item(s) at the given offset(s).
If ignoreSort is True then the inserting does not change whether the Stream is sorted or not (much faster if you’re going to be inserting dozens of items that don’t change the sort status)
The setActiveSite parameter should nearly always be True; only for advanced Stream manipulation would you not change the activeSite after inserting an element.
Has three forms: in the two argument form, inserts an element at the given offset:
>>> from music21 import * >>> st1 = stream.Stream() >>> st1.insert(32, note.Note("B-")) >>> st1.highestOffset 32.0In the single argument form with an object, inserts the element at its stored offset:
>>> n1 = note.Note("C#") >>> n1.offset = 30.0 >>> st1 = stream.Stream() >>> st1.insert(n1) >>> st2 = stream.Stream() >>> st2.insert(40.0, n1) >>> n1.getOffsetBySite(st1) 30.0In single argument form with a list, the list should contain pairs that alternate offsets and items; the method then, obviously, inserts the items at the specified offsets:
>>> n1 = note.Note("G") >>> n2 = note.Note("F#") >>> st3 = stream.Stream() >>> st3.insert([1.0, n1, 2.0, n2]) >>> n1.getOffsetBySite(st3) 1.0 >>> n2.getOffsetBySite(st3) 2.0 >>> len(st3) 2
- insertAndShift(offsetOrItemOrList, itemOrNone=None)¶
Insert an item at a specified or native offset, and shit any elements found in the Stream to start at the end of the added elements.
This presently does not shift elements that have durations that extend into the lowest insert position.
>>> from music21 import * >>> st1 = stream.Stream() >>> st1.insertAndShift(32, note.Note("B-")) >>> st1.highestOffset 32.0 >>> st1.insertAndShift(32, note.Note("B-")) >>> st1.highestOffset 33.0In the single argument form with an object, inserts the element at its stored offset:
>>> n1 = note.Note("C#") >>> n1.offset = 30.0 >>> n2 = note.Note("C#") >>> n2.offset = 30.0 >>> st1 = stream.Stream() >>> st1.insertAndShift(n1) >>> st1.insertAndShift(n2) # should shift offset of n1 >>> n1.getOffsetBySite(st1) 31.0 >>> n2.getOffsetBySite(st1) 30.0 >>> st2 = stream.Stream() >>> st2.insertAndShift(40.0, n1) >>> st2.insertAndShift(40.0, n2) >>> n1.getOffsetBySite(st2) 41.0In single argument form with a list, the list should contain pairs that alternate offsets and items; the method then, obviously, inserts the items at the specified offsets:
>>> n1 = note.Note("G") >>> n2 = note.Note("F#") >>> st3 = stream.Stream() >>> st3.insertAndShift([1.0, n1, 2.0, n2]) >>> n1.getOffsetBySite(st3) 1.0 >>> n2.getOffsetBySite(st3) 2.0 >>> len(st3) 2N.B. – using this method on a list assumes that you’ll be inserting contiguous objects; you can’t shift things that are separated, as this following FAILED example shows.
>>> n1 = note.HalfNote('G') >>> st4 = stream.Stream() >>> st4.repeatAppend(n1, 3) >>> st4.insertAndShift([2.0, note.Note('e'), 4.0, note.Note('f')]) >>> st4.show('text') {0.0} <music21.note.Note G> {2.0} <music21.note.Note E> {4.0} <music21.note.Note F> {5.0} <music21.note.Note G> {7.0} <music21.note.Note G>
- transpose(value, inPlace=False, classFilterList=['Note', 'Chord'])¶
Transpose all specified classes in the Stream by the user-provided value. If the value is an integer, the transposition is treated in half steps. If the value is a string, any Interval string specification can be provided.
returns a new Stream by default, but if the optional “inPlace” key is set to True then it modifies pitches in place.
>>> from music21 import * >>> aInterval = interval.Interval('d5')>>> aStream = corpus.parse('bach/bwv324.xml') >>> part = aStream.parts[0] >>> aStream.parts[0].pitches[:10] [B4, D5, B4, B4, B4, B4, C5, B4, A4, A4] >>> bStream = aStream.parts[0].flat.transpose('d5') >>> bStream.pitches[:10] [F5, A-5, F5, F5, F5, F5, G-5, F5, E-5, E-5] >>> aStream.parts[0].pitches[:10] [B4, D5, B4, B4, B4, B4, C5, B4, A4, A4] >>> cStream = bStream.flat.transpose('a4') >>> cStream.pitches[:10] [B5, D6, B5, B5, B5, B5, C6, B5, A5, A5] >>> cStream.flat.transpose(aInterval, inPlace=True) >>> cStream.pitches[:10] [F6, A-6, F6, F6, F6, F6, G-6, F6, E-6, E-6]
- augmentOrDiminish(amountToScale, inPlace=False)¶
Given a number greater than zero, multiplies the current quarterLength of the duration of each element by this number as well as their offset and returns a new Stream. Or if inPlace is set to True, modifies the durations of each element within the stream.
A number of .5 will halve the durations and relative offset positions; a number of 2 will double the durations and relative offset positions.
Note that the default for inPlace is the opposite of what it is for augmentOrDiminish on a Duration. This is done purposely to reflect the most common usage.
>>> from music21 import * >>> s = stream.Stream() >>> n = note.Note() >>> s.repeatAppend(n, 10) >>> s.highestOffset, s.highestTime (9.0, 10.0) >>> s1 = s.augmentOrDiminish(2) >>> s1.highestOffset, s1.highestTime (18.0, 20.0) >>> s1 = s.augmentOrDiminish(.5) >>> s1.highestOffset, s1.highestTime (4.5, 5.0)
- scaleOffsets(amountToScale, anchorZero='lowest', anchorZeroRecurse=None, inPlace=True)¶
Scale all offsets by a multiplication factor given in amountToScale. Durations are not altered.
To augment or diminish a Stream, see the augmentOrDiminish() method.
The anchorZero parameter determines if and/or where the zero offset is established for the set of offsets in this Stream before processing. Offsets are shifted to make either the lower or upper values the new zero; then offsets are scaled; then the shifts are removed. Accepted values are None (no offset shifting), “lowest”, or “highest”.
The anchorZeroRecurse parameter determines the anchorZero for all embedded Streams, and Streams embedded within those Streams. If the lowest offset in an embedded Stream is non-zero, setting this value to None will a the space between the start of that Stream and the first element to be scaled. If the lowest offset in an embedded Stream is non-zero, setting this value to ‘lowest’ will not alter the space between the start of that Stream and the first element to be scaled.
To shift all the elements in a Stream, see the shiftElements() method.
- scaleDurations(amountToScale, inPlace=True)¶
Scale all durations by a provided scalar. Offsets are not modified.
To augment or diminish a Stream, see the augmentOrDiminish() method.
- activateVariants(group=None, matchBySpan=True, inPlace=False)¶
For any Variant objects defined in this Stream (or selected by matching the group parameter), replace elements defined in the Variant with those in the calling Stream. Elements replaced will be gathered into a new Variant given the group ‘default’. If a variant is activated with .replacementDuration different from its length, the appropriate elements in the stream will have their offsets shifted, and measure numbering will be fixed. If matchBySpan is True, variants with lengthType ‘replacement’ will replace all of the elements in the replacement region of comparable class. If matchBySpan is False, elements will be swapped in when a match is found between an element in the variant and an element in the replcement region of the string.
>>> from music21 import * >>> s = converter.parse("d4 e4 f4 g4 a2 b-4 a4 g4 a8 g8 f4 e4 d2 a2 d4 e4 f4 g4 a2 b-4 a4 g4 a8 b-8 c'4 c4 f1", "4/4") >>> s.makeMeasures(inPlace = True) >>> v1stream = converter.parse(" a2. b-8 a8", "4/4") >>> v2stream1 = converter.parse(" d4 f4 a2", "4/4") >>> v2stream2 = converter.parse(" d4 f4 AA2", "4/4") >>> v1 = variant.Variant() >>> v1measure = stream.Measure() >>> v1.insert(0.0, v1measure) >>> for e in v1stream.notesAndRests: ... v1measure.insert(e.offset, e)>>> v2 = variant.Variant() >>> v2measure1 = stream.Measure() >>> v2measure2 = stream.Measure() >>> v2.insert(0.0, v2measure1) >>> v2.insert(4.0, v2measure2) >>> for e in v2stream1.notesAndRests: ... v2measure1.insert(e.offset, e) >>> for e in v2stream2.notesAndRests: ... v2measure2.insert(e.offset, e) >>> v3 = variant.Variant() >>> v2.replacementDuration = 4.0 >>> v3.replacementDuration = 4.0 >>> v1.groups = ["docvariants"] >>> v2.groups = ["docvariants"] >>> v3.groups = ["docvariants"]>>> s.insert(4.0, v1) # replacement variant >>> s.insert(12.0, v2) # insertion variant (2 bars replace 1 bar) >>> s.insert(20.0, v3) # deletion variant (0 bars replace 1 bar) >>> docvariant = s.activateVariants('docvariants')>>> s.show()
>>> docvariant.show()
>>> docvariant.show('text') {0.0} <music21.stream.Measure 1 offset=0.0> {0.0} <music21.clef.TrebleClef> {0.0} <music21.meter.TimeSignature 4/4> {0.0} <music21.note.Note D> {1.0} <music21.note.Note E> {2.0} <music21.note.Note F> {3.0} <music21.note.Note G> {4.0} <music21.variant.Variant object at ...> {4.0} <music21.stream.Measure 2 offset=4.0> {0.0} <music21.note.Note A> {3.0} <music21.note.Note B-> {3.5} <music21.note.Note A> {8.0} <music21.stream.Measure 3 offset=8.0> {0.0} <music21.note.Note G> {1.0} <music21.note.Note A> {1.5} <music21.note.Note G> {2.0} <music21.note.Note F> {3.0} <music21.note.Note E> {12.0} <music21.variant.Variant object at ...> {12.0} <music21.stream.Measure 4 offset=12.0> {0.0} <music21.note.Note D> {1.0} <music21.note.Note F> {2.0} <music21.note.Note A> {16.0} <music21.stream.Measure 5 offset=16.0> {0.0} <music21.note.Note D> {1.0} <music21.note.Note F> {2.0} <music21.note.Note A> {20.0} <music21.stream.Measure 6 offset=20.0> {0.0} <music21.note.Note D> {1.0} <music21.note.Note E> {2.0} <music21.note.Note F> {3.0} <music21.note.Note G> {24.0} <music21.variant.Variant object at ...> {24.0} <music21.stream.Measure 7 offset=24.0> {0.0} <music21.note.Note G> {1.0} <music21.note.Note A> {1.5} <music21.note.Note B-> {2.0} <music21.note.Note C> {3.0} <music21.note.Note C> {28.0} <music21.stream.Measure 8 offset=28.0> {0.0} <music21.note.Note F> {4.0} <music21.bar.Barline style=final>After a variant group has been activated, the regions it replaced are stored as variants with the group ‘default’. It should be noted that this means .activateVariants should rarely if ever be used on a stream which is returned by activateVariants because the group information is lost.
>>> defaultvariant = docvariant.activateVariants('default') >>> defaultvariant.show()
>>> defaultvariant.show('text') {0.0} <music21.stream.Measure 1 offset=0.0> {0.0} <music21.clef.TrebleClef> {0.0} <music21.meter.TimeSignature 4/4> {0.0} <music21.note.Note D> {1.0} <music21.note.Note E> {2.0} <music21.note.Note F> {3.0} <music21.note.Note G> {4.0} <music21.variant.Variant object at ...> {4.0} <music21.stream.Measure 2 offset=4.0> {0.0} <music21.note.Note A> {2.0} <music21.note.Note B-> {3.0} <music21.note.Note A> {8.0} <music21.stream.Measure 3 offset=8.0> {0.0} <music21.note.Note G> {1.0} <music21.note.Note A> {1.5} <music21.note.Note G> {2.0} <music21.note.Note F> {3.0} <music21.note.Note E> {12.0} <music21.variant.Variant object at ...> {12.0} <music21.stream.Measure 4 offset=12.0> {0.0} <music21.note.Note D> {2.0} <music21.note.Note A> {16.0} <music21.stream.Measure 5 offset=16.0> {0.0} <music21.note.Note D> {1.0} <music21.note.Note E> {2.0} <music21.note.Note F> {3.0} <music21.note.Note G> {20.0} <music21.variant.Variant object at ...> {20.0} <music21.stream.Measure 6 offset=20.0> {0.0} <music21.note.Note A> {2.0} <music21.note.Note B-> {3.0} <music21.note.Note A> {24.0} <music21.stream.Measure 7 offset=24.0> {0.0} <music21.note.Note G> {1.0} <music21.note.Note A> {1.5} <music21.note.Note B-> {2.0} <music21.note.Note C> {3.0} <music21.note.Note C> {28.0} <music21.stream.Measure 8 offset=28.0> {0.0} <music21.note.Note F> {4.0} <music21.bar.Barline style=final>
- addGroupForElements(group, classFilter=None)¶
Add the group to the groups attribute of all elements. if classFilter is set then only those elements whose objects belong to a certain class (or for Streams which are themselves of a certain class) are set.
>>> from music21 import * >>> a = stream.Stream() >>> a.repeatAppend(note.Note('A-'), 30) >>> a.repeatAppend(note.Rest(), 30) >>> a.addGroupForElements('flute') >>> a[0].groups ['flute'] >>> a.addGroupForElements('quietTime', note.Rest) >>> a[0].groups ['flute'] >>> a[50].groups ['flute', 'quietTime'] >>> a[1].groups.append('quietTime') # set one note to it >>> a[1].step = "B" >>> b = a.getElementsByGroup('quietTime') >>> len(b) 31 >>> c = b.getElementsByClass(note.Note) >>> len(c) 1 >>> c[0].name 'B-'
- allPlayingWhileSounding(el, elStream=None, requireClass=False)¶
Returns a new Stream of elements in this stream that sound at the same time as el, an element presumably in another Stream.
The offset of this new Stream is set to el’s offset, while the offset of elements within the Stream are adjusted relative to their position with respect to the start of el. Thus, a note that is sounding already when el begins would have a negative offset. The duration of otherStream is forced to be the length of el – thus a note sustained after el ends may have a release time beyond that of the duration of the Stream.
as above, elStream is an optional Stream to look up el’s offset in.
The method always returns a Stream, but it might be an empty Stream.
- analyze(*args, **keywords)¶
Runs a particular analytical method on the contents of the stream to find its ambitus (range) or key.
ambitus – runs Ambitus key – runs KrumhanslSchmuckler
Some of these methods can take additional arguments. For details on these arguments, see analyzeStream().
Example:
>>> from music21 import * >>> s = corpus.parse('bach/bwv66.6') >>> s.analyze('ambitus') <music21.interval.Interval m21> >>> s.analyze('key') <music21.key.Key of f# minor>Example: music21 allows you to automatically run an analysis to get the key of a piece or excerpt not based on the key signature but instead on the frequency with which some notes are used as opposed to others (first described by Carol Krumhansl). For instance, a piece with mostly Cs and Gs, some Fs, and Ds, but fewer G#s, C#s, etc. is more likely to be in the key of C major than in D-flat major (or A minor, etc.). You can easily get this analysis from a stream by running:
>>> myStream = corpus.parse('luca/gloria') >>> analyzedKey = myStream.analyze('key') >>> analyzedKey <music21.key.Key of F major>analyzedKey is a Key object with a few extra parameters. correlationCoefficient shows how well this key fits the profile of a piece in that key:
>>> analyzedKey.correlationCoefficient 0.86715...alternateInterpretations is a list of the other possible interpretations sorted from most likely to least:
>>> analyzedKey.alternateInterpretations [<music21.key.Key of d minor>, <music21.key.Key of C major>, <music21.key.Key of g minor>,...]Each of these can be examined in turn to see its correlation coefficient:
>>> analyzedKey.alternateInterpretations[1].correlationCoefficient 0.788528... >>> analyzedKey.alternateInterpretations[22].correlationCoefficient -0.86728...
- attachIntervalsBetweenStreams(cmpStream)¶
For each element in self, creates an interval.Interval object in the element’s editorial that is the interval between it and the element in cmpStream that is sounding at the moment the element in srcStream is attacked.
Remember that if you are comparing two streams with measures, etc., you’ll need to flatten each stream as follows:
>>> stream1.flat.attachIntervalsBetweenStreams(stream2.flat)Example usage:
>>> from music21 import * >>> s1 = converter.parse('C4 d8 e f# g A2 d2', '7/4') >>> s2 = converter.parse('g4 e8 d c4 a2 r2', '7/4') >>> s1.attachIntervalsBetweenStreams(s2) >>> for n in s1.notes: ... if n.editorial.harmonicInterval is None: print "None" # if other voice had a rest... ... else: print n.editorial.harmonicInterval.directedName P12 M2 M-2 A-4 P-5 P8 None
- attachMelodicIntervals()¶
For each element in self, creates an interval.Interval object in the element’s editorial that is the interval between it and the previous element in the stream. Thus, the first element will have a value of None.
>>> from music21 import * >>> s1 = converter.parse('C4 d8 e f# g A2 d2', '7/4') >>> s1.attachMelodicIntervals() >>> for n in s1.notes: ... if n.editorial.melodicInterval is None: print None ... else: print n.editorial.melodicInterval.directedName None M9 M2 M2 m2 m-7 P4
- attributeCount(classFilterList, attrName='quarterLength')¶
Return a dictionary of attribute usage for one or more classes provided in a the classFilterList list and having the attribute specified by attrName.
>>> from music21 import corpus >>> a = corpus.parse('bach/bwv324.xml') >>> a.parts[0].flat.attributeCount(note.Note, 'quarterLength') {1.0: 12, 2.0: 11, 4.0: 2}
- bestClef(allowTreble8vb=False)¶
Returns the clef that is the best fit for notes and chords found in this Stream.
This does not automatically get a flat representation of the Stream.
>>> from music21 import * >>> a = stream.Stream() >>> for x in range(30): ... n = note.Note() ... n.midi = random.choice(range(60,72)) ... a.insert(n) >>> b = a.bestClef() >>> b.line 2 >>> b.sign 'G' >>> c = stream.Stream() >>> for x in range(30): ... n = note.Note() ... n.midi = random.choice(range(35,55)) ... c.insert(n) >>> d = c.bestClef() >>> d.line 4 >>> d.sign 'F'
- chordify(addTies=True, displayTiedAccidentals=False, addPartIdAsGroup=False, removeRedundantPitches=True, toSoundingPitch=True)¶
Create a chordal reduction of polyphonic music, where each change to a new pitch results in a new chord. If a Score or Part of Measures is provided, a Stream of Measures will be returned. If a flat Stream of notes, or a Score of such Streams is provided, no Measures will be returned.
If using chordify with chord symbols, ensure that the chord symbols have durations (by default the duration of a chord symbol object is 0, unlike a chord object). If harmony objects are not provided a duration, they will not be included in the chordified output pitches but may appear as chord symbol in notation on the score. To realize the chord symbol durations on a score, call music21.harmony.realizeChordSymbolDurations() and pass in the score.
This functionlaity works by splitting all Durations in all parts, or if multi-part by all unique offsets. All simultaneous durations are then gathered into single chords.
If addPartIdAsGroup is True, all elements found in the Stream will have their source Part id added to the element’s Group. These groups names are useful for partially “de-chordifying” the output.
The addTies parameter currently does not work for pitches in Chords.
If toSoundingPitch is True, all parts that define one or more transpositions will be transposed to sounding pitch before chordification. True by default.
>>> from music21 import * >>> s = stream.Score() >>> p1 = stream.Part() >>> p1.insert(4, note.Note("C#")) >>> p1.insert(5.3, note.Rest()) >>> p2 = stream.Part() >>> p2.insert(2.12, note.HalfNote("D-")) >>> p2.insert(5.5, note.Rest()) >>> s.insert(0, p1) >>> s.insert(0, p2) >>> cc = s.chordify() >>> cc.show('text') {0.0} <music21.note.Rest rest> {2.12} <music21.chord.Chord D-> {4.0} <music21.chord.Chord C# D-> {4.12} <music21.chord.Chord C#> {5.0} <music21.note.Rest rest>>>> s = stream.Stream() >>> p1 = stream.Part() >>> p1.insert(0, harmony.ChordSymbol('Cm', quarterLength = 4.0)) >>> p1.insert(2, note.Note('C')) >>> p1.insert(4, harmony.ChordSymbol('D', quarterLength = 4.0)) >>> p1.insert(7, note.Note('A')) >>> s.insert(0,p1) >>> s.chordify().show('text') {0.0} <music21.chord.Chord C3 E-3 G3> {2.0} <music21.chord.Chord C C3 E-3 G3> {3.0} <music21.chord.Chord C3 E-3 G3> {4.0} <music21.chord.Chord D3 F#3 A3> {7.0} <music21.chord.Chord A D3 F#3 A3>
- expandRepeats(copySpanners=True)¶
Expand this Stream with repeats. Nested repeats given with Repeat objects, or repeats and sections designated with RepeatExpression objects, are all expanded.
This method always returns a new Stream, with deepcopies of all contained elements at all levels.
Uses the Expander object in the repeat module.
TODO: DOC TEST
- explode()¶
Create a multi-part extraction from a single polyphonic Part.
Currently just runs voicesToParts() but that will change as part explosion develops, and this method will use our best available quick method for part extraction.
- extendDuration(objName, inPlace=True)¶
Given a Stream and an object class name, go through the Stream and find each instance of the desired object. The time between adjacent objects is then assigned to the duration of each object. The last duration of the last object is assigned to extend to the end of the Stream.
If inPlace is True, this is done in-place; if inPlace is False, this returns a modified deep copy.
>>> from music21 import * >>> stream1 = stream.Stream() >>> n = note.QuarterNote() >>> n.duration.quarterLength 1.0 >>> stream1.repeatInsert(n, [0, 10, 20, 30, 40])>>> dyn = dynamics.Dynamic('ff') >>> stream1.insert(15, dyn) >>> sort1 = stream1.sorted >>> sort1[-1].offset # offset of last element 40.0 >>> sort1.duration.quarterLength # total duration 41.0 >>> len(sort1) 6>>> stream2 = sort1.flat.extendDuration(note.GeneralNote) >>> len(stream2) 6 >>> stream2[0].duration.quarterLength 10.0 >>> stream2[1].duration.quarterLength # all note durs are 10 10.0 >>> stream2[-1].duration.quarterLength # or extend to end of stream 1.0 >>> stream2.duration.quarterLength 41.0 >>> stream2[-1].offset 40.0
- extendDurationAndGetBoundaries(objName, inPlace=True)¶
Extend the Duration of elements specified by objName; then, collect a dictionary for every matched element of objName class, where the matched element is the value and the key is the start,end offset value.
>>> from music21 import * >>> s = stream.Stream() >>> s.insert(3, dynamics.Dynamic('mf')) >>> s.insert(7, dynamics.Dynamic('f')) >>> s.insert(12, dynamics.Dynamic('ff')) >>> s.extendDurationAndGetBoundaries('Dynamic') {(7.0, 12.0): <music21.dynamics.Dynamic f >, (3.0, 7.0): <music21.dynamics.Dynamic mf >, (12.0, 12.0): <music21.dynamics.Dynamic ff >}
- extendTies(ignoreRests=False, pitchAttr='nameWithOctave')¶
Connect any adjacent pitch space values that are the same with a Tie. Adjacent pitches can be Chords, Notes, or Voices.
If ignoreRests is True, rests that occur between events will not be considered in matching pitches.
The pitchAttr determines the pitch attribute that is used for comparison. Any valid pitch attribute name can be used.
- extractContext(searchElement, before=4.0, after=4.0, maxBefore=None, maxAfter=None, forceOutputClass=None)¶
Extracts elements around the given element within (before) quarter notes and (after) quarter notes (default 4), and returns a new Stream.
>>> from music21 import * >>> qn = note.QuarterNote() >>> qtrStream = stream.Stream() >>> qtrStream.repeatInsert(qn, [0, 1, 2, 3, 4, 5]) >>> hn = note.HalfNote() >>> hn.name = "B-" >>> qtrStream.append(hn) >>> qtrStream.repeatInsert(qn, [8, 9, 10, 11]) >>> hnStream = qtrStream.extractContext(hn, 1.0, 1.0) >>> hnStream.show('text') {5.0} <music21.note.Note C> {6.0} <music21.note.Note B-> {8.0} <music21.note.Note C>
- findConsecutiveNotes(skipRests=False, skipChords=False, skipUnisons=False, skipOctaves=False, skipGaps=False, getOverlaps=False, noNone=False, **keywords)¶
Returns a list of consecutive pitched Notes in a Stream. A single “None” is placed in the list at any point there is a discontinuity (such as if there is a rest between two pitches), unless the noNone parameter is True.
How to determine consecutive pitches is a little tricky and there are many options.
The skipUnison parameter uses the midi-note value (.ps) to determine unisons, so enharmonic transitions (F# -> Gb) are also skipped if skipUnisons is true. We believe that this is the most common usage. However, because of this, you cannot completely be sure that the x.findConsecutiveNotes() - x.findConsecutiveNotes(skipUnisons = True) will give you the number of P1s in the piece, because there could be d2’s in there as well.
See Test.testFindConsecutiveNotes() for usage details.
- findGaps(minimumQuarterLength=0.001)¶
Returns either (1) a Stream containing Elements (that wrap the None object) whose offsets and durations are the length of gaps in the Stream or (2) None if there are no gaps.
N.B. there may be gaps in the flattened representation of the stream but not in the unflattened. Hence why “isSequence” calls self.flat.isGapless
- flattenUnnecessaryVoices(force=False, inPlace=True)¶
If this Stream defines one or more internal voices, do the following:
- If there is more than one voice, and a voice has no elements, remove that voice.
- If there is only one voice left that has elements, place those elements in the parent Stream.
- If force is True, even if there is more than one Voice left, all voices will be flattened.
- getClefs(searchActiveSite=False, searchContext=True, returnDefault=True)¶
Collect all Clef objects in this Stream in a new Stream. Optionally search the activeSite Stream and/or contexts.
If no Clef objects are defined, get a default using bestClef()
>>> from music21 import * >>> a = stream.Stream() >>> b = clef.AltoClef() >>> a.insert(0, b) >>> a.repeatInsert(note.Note("C#"), range(10)) >>> c = a.getClefs() >>> len(c) == 1 True
- getElementAfterElement(element, classList=None)¶
given an element, get the next element. If classList is specified, check to make sure that the element is an instance of the class list
>>> from music21 import * >>> st1 = stream.Stream() >>> n1 = note.Note() >>> n2 = note.Note() >>> r3 = note.Rest() >>> st1.append([n1, n2, r3]) >>> t2 = st1.getElementAfterElement(n1) >>> t2 is n2 True >>> t3 = st1.getElementAfterElement(t2) >>> t3 is r3 True >>> t4 = st1.getElementAfterElement(t3) >>> t4>>> st1.getElementAfterElement("hi") Traceback (most recent call last): StreamException: ... >>> t5 = st1.getElementAfterElement(n1, [note.Rest]) >>> t5 is r3 True >>> t6 = st1.getElementAfterElement(n1, [note.Rest, note.Note]) >>> t6 is n2 True
- getElementAfterOffset(offset, classList=None)¶
Get element after a provided offset
TODO: write this
- getElementAtOrAfter(offset, classList=None)¶
Given an offset, find the element at this offset, or with the offset greater than and nearest to.
TODO: write this
- getElementAtOrBefore(offset, classList=None)¶
Given an offset, find the element at this offset, or with the offset less than and nearest to.
Return one element or None if no elements are at or preceded by this offset.
If the classList parameter is provided with a list of class names or strings, the only objects that will returned are objects that are instances of these classes or subclasses of these classes.
>>> from music21 import * >>> stream1 = stream.Stream() >>> x = note.Note('D4') >>> x.id = 'x' >>> y = note.Note('E4') >>> y.id = 'y' >>> z = note.Rest() >>> z.id = 'z'>>> stream1.insert(20, x) >>> stream1.insert(10, y) >>> stream1.insert( 0, z) >>> b = stream1.getElementAtOrBefore(21) >>> b.offset, b.id (20.0, 'x')>>> b = stream1.getElementAtOrBefore(19) >>> b.offset, b.id (10.0, 'y') >>> b = stream1.getElementAtOrBefore(0) >>> b.offset, b.id (0.0, 'z') >>> b = stream1.getElementAtOrBefore(0.1) >>> b.offset, b.id (0.0, 'z')You can give a list of acceptable classes to return, and non-matching elements will be ignored
>>> c = stream1.getElementAtOrBefore(100, [music21.clef.TrebleClef, music21.note.Rest]) >>> c.offset, c.id (0.0, 'z')Getting an object via getElementAtOrBefore sets the activeSite for that object to the Stream, and thus sets its offset
>>> stream2 = stream.Stream() >>> stream2.insert(100.5, x) >>> x.offset 100.5 >>> d = stream1.getElementAtOrBefore(20) >>> d is x True >>> x.activeSite is stream1 True >>> x.offset 20.0
- getElementBeforeElement(element, classList=None)¶
given an element, get the element before
TODO: write this
- getElementBeforeOffset(offset, classList=None)¶
Get element before (and not at) a provided offset.
If the classList parameter is provided with a list of class names or strings, the only objects that will returned are objects that are instances of these classes or subclasses of these classes.
>>> from music21 import * >>> stream1 = stream.Stream() >>> x = note.Note('D4') >>> x.id = 'x' >>> y = note.Note('E4') >>> y.id = 'y' >>> z = note.Rest() >>> z.id = 'z' >>> stream1.insert(20, x) >>> stream1.insert(10, y) >>> stream1.insert( 0, z) >>> b = stream1.getElementBeforeOffset(21) >>> b.offset, b.id (20.0, 'x') >>> b = stream1.getElementBeforeOffset(20) >>> b.offset, b.id (10.0, 'y')>>> b = stream1.getElementBeforeOffset(10) >>> b.offset, b.id (0.0, 'z') >>> b = stream1.getElementBeforeOffset(0) >>> b == None True >>> b = stream1.getElementBeforeOffset(0.1) >>> b.offset, b.id (0.0, 'z')
- getElementById(id, classFilter=None)¶
Returns the first encountered element for a given id. Return None if no match. Note: this uses the id attribute stored on elements, which may not be the same as id(e).
>>> from music21 import * >>> a = stream.Stream() >>> ew = note.Note() >>> a.insert(0, ew) >>> a[0].id = 'green' >>> None == a.getElementById(3) True >>> a.getElementById('green').id 'green' >>> a.getElementById('Green').id # case does not matter 'green'Getting an element by getElementById changes its activeSite
>>> b = stream.Stream() >>> b.append(ew) >>> ew.activeSite is b True >>> ew2 = a.getElementById('green') >>> ew2 is ew True >>> ew2.activeSite is a True >>> ew.activeSite is a True
- getElementByObjectId(objId)¶
Low-level tool to get an element based only on the object id.
This is not the same as getElementById, which refers to the id attribute which may be manually set and not unique.
- getElementsByClass(classFilterList, returnStreamSubClass=True)¶
Return a list of all Elements that match one or more classes in the classFilterList. A single class can be provided to the classFilterList parameter.
>>> from music21 import * >>> a = stream.Score() >>> a.repeatInsert(note.Rest(), range(10)) >>> for x in range(4): ... n = note.Note('G#') ... n.offset = x * 3 ... a.insert(n) >>> found = a.getElementsByClass(note.Note) >>> len(found) 4 >>> found[0].pitch.accidental.name 'sharp' >>> b = stream.Stream() >>> b.repeatInsert(note.Rest(), range(15)) >>> a.insert(b) >>> # here, it gets elements from within a stream >>> # this probably should not do this, as it is one layer lower >>> found = a.getElementsByClass(note.Rest) >>> len(found) 10 >>> found = a.flat.getElementsByClass(note.Rest) >>> len(found) 25 >>> found.__class__.__name__ 'Score'
- getElementsByGroup(groupFilterList)¶
>>> from music21 import * >>> n1 = note.Note("C") >>> n1.groups.append('trombone') >>> n2 = note.Note("D") >>> n2.groups.append('trombone') >>> n2.groups.append('tuba') >>> n3 = note.Note("E") >>> n3.groups.append('tuba') >>> s1 = stream.Stream() >>> s1.append(n1) >>> s1.append(n2) >>> s1.append(n3) >>> tboneSubStream = s1.getElementsByGroup("trombone") >>> for thisNote in tboneSubStream: ... print(thisNote.name) C D >>> tubaSubStream = s1.getElementsByGroup("tuba") >>> for thisNote in tubaSubStream: ... print(thisNote.name) D E
- getElementsByOffset(offsetStart, offsetEnd=None, includeEndBoundary=True, mustFinishInSpan=False, mustBeginInSpan=True, classList=None)¶
Returns a Stream containing all Music21Objects that are found at a certain offset or within a certain offset time range (given the start and optional stop values).
There are several attributes that govern how this range is determined:
If mustFinishInSpan is True then an event that begins between offsetStart and offsetEnd but which ends after offsetEnd will not be included. The default is False.
For instance, a half note at offset 2.0 will be found in getElementsByOffset(1.5, 2.5) or getElementsByOffset(1.5, 2.5, mustFinishInSpan = False) but not by getElementsByOffset(1.5, 2.5, mustFinishInSpan = True).
The includeEndBoundary option determines if an element begun just at the offsetEnd should be included. For instance, the half note at offset 2.0 above would be found by getElementsByOffset(0, 2.0) or by getElementsByOffset(0, 2.0, includeEndBoundary = True) but not by getElementsByOffset(0, 2.0, includeEndBoundary = False).
Setting includeEndBoundary to False at the same time as mustFinishInSpan is set to True is probably NOT what you want to do unless you want to find things like clefs at the end of the region to display as courtesy clefs.
The mustBeginInSpan option determines whether notes or other objects that do not begin in the region but are still sounding at the beginning of the region are excluded. The default is True – that is, these notes will not be included. For instance the half note at offset 2.0 from above would not be found by getElementsByOffset(3.0, 3.5) or getElementsByOffset(3.0, 3.5, mustBeginInSpan = True) but it would be found by getElementsByOffset(3.0, 3.5, mustBeginInSpan = False)
This chart, and the examples below, demonstrate the various features of getElementsByOffset. It is one of the most complex methods of music21 but also one of the most powerful, so it is worth learning at least the basics.
>>> from music21 import * >>> st1 = stream.Stream() >>> n0 = note.Note("C") >>> n0.duration.type = "half" >>> n0.offset = 0 >>> st1.insert(n0) >>> n2 = note.Note("D") >>> n2.duration.type = "half" >>> n2.offset = 2 >>> st1.insert(n2) >>> out1 = st1.getElementsByOffset(2) >>> len(out1) 1 >>> out1[0].step 'D' >>> out2 = st1.getElementsByOffset(1, 3) >>> len(out2) 1 >>> out2[0].step 'D' >>> out3 = st1.getElementsByOffset(1, 3, mustFinishInSpan = True) >>> len(out3) 0 >>> out4 = st1.getElementsByOffset(1, 2) >>> len(out4) 1 >>> out4[0].step 'D' >>> out5 = st1.getElementsByOffset(1, 2, includeEndBoundary = False) >>> len(out5) 0 >>> out6 = st1.getElementsByOffset(1, 2, includeEndBoundary = False, mustBeginInSpan = False) >>> len(out6) 1 >>> out6[0].step 'C' >>> out7 = st1.getElementsByOffset(1, 3, mustBeginInSpan = False) >>> len(out7) 2 >>> [el.step for el in out7] ['C', 'D']>>> a = stream.Stream() >>> n = note.Note('G') >>> n.quarterLength = .5 >>> a.repeatInsert(n, range(8)) >>> b = stream.Stream() >>> b.repeatInsert(a, [0, 3, 6]) >>> c = b.getElementsByOffset(2,6.9) >>> len(c) 2 >>> c = b.flat.getElementsByOffset(2,6.9) >>> len(c) 10
- getElementsNotOfClass(classFilterList)¶
Return a list of all Elements that do not match the one or more classes in the classFilterList. A single class can be provided to the classFilterList parameter.
>>> from music21 import * >>> a = stream.Stream() >>> a.repeatInsert(note.Rest(), range(10)) >>> for x in range(4): ... n = note.Note('G#') ... n.offset = x * 3 ... a.insert(n) >>> found = a.getElementsNotOfClass(note.Note) >>> len(found) 10>>> b = stream.Stream() >>> b.repeatInsert(note.Rest(), range(15)) >>> a.insert(b) >>> # here, it gets elements from within a stream >>> # this probably should not do this, as it is one layer lower >>> found = a.flat.getElementsNotOfClass(note.Rest) >>> len(found) 4 >>> found = a.flat.getElementsNotOfClass(note.Note) >>> len(found) 25
- getInstrument(searchActiveSite=True, returnDefault=True)¶
Return the first Instrument found in this Stream.
- getInstruments(searchActiveSite=True, returnDefault=True)¶
Search this stream or activeSite streams for Instrument objects, otherwise return a default Instrument
>>> from music21 import * >>> s = stream.Score() >>> p1 = stream.Part() >>> p1.insert(instrument.Violin()) >>> m1p1 = stream.Measure() >>> m1p1.append(note.Note('g')) >>> p1.append(m1p1) >>> p2 = stream.Part() >>> p2.insert(instrument.Viola()) >>> m1p2 = stream.Measure() >>> m1p2.append(note.Note('f#')) >>> p2.append(m1p2)>>> s.insert(0, p1) >>> s.insert(0, p2) >>> p1.getInstrument(returnDefault=False).instrumentName 'Violin' >>> p2.getInstrument(returnDefault=False).instrumentName 'Viola'
- getKeySignatures(searchActiveSite=True, searchContext=True)¶
Collect all KeySignature objects in this Stream in a new Stream. Optionally search the activeSite stream and/or contexts.
If no KeySignature objects are defined, returns an empty Stream
>>> from music21 import * >>> a = stream.Stream() >>> b = key.KeySignature(3) >>> a.insert(0, b) >>> a.repeatInsert(note.Note("C#"), range(10)) >>> c = a.getKeySignatures() >>> len(c) == 1 True
- getOffsetByElement(obj)¶
Given an object, return the offset of that object in the context of this Stream. This method can be called on a flat representation to return the ultimate position of a nested structure.
If the object is not found in the Stream, None is returned.
>>> from music21 import * >>> n1 = note.Note('A') >>> n2 = note.Note('B')>>> s1 = stream.Stream() >>> s1.insert(10, n1) >>> s1.insert(100, n2) >>> s2 = stream.Stream() >>> s2.insert(10, s1)>>> s2.flat.getOffsetBySite(n1) # this will not work Traceback (most recent call last): DefinedContextsException: ... >>> s2.flat.getOffsetByElement(n1) 20.0 >>> s2.flat.getOffsetByElement(n2) 110.0
- getOverlaps(includeDurationless=True, includeEndBoundary=False)¶
Find any elements that overlap. Overlaping might include elements that have no duration but that are simultaneous. Whether elements with None durations are included is determined by includeDurationless.
This method returns a dictionary, where keys are the start time of the first overlap and value are a list of all objects included in that overlap group.
This example demonstrates end-joing overlaps: there are four quarter notes each following each other. Whether or not these count as overlaps is determined by the includeEndBoundary parameter.
>>> from music21 import * >>> a = stream.Stream() >>> for x in range(4): ... n = note.Note('G#') ... n.duration = duration.Duration('quarter') ... n.offset = x * 1 ... a.insert(n) ... >>> d = a.getOverlaps(True, False) >>> len(d) 0 >>> d = a.getOverlaps(True, True) # including coincident boundaries >>> len(d) 1 >>> len(d[0]) 4 >>> a = stream.Stream() >>> for x in [0,0,0,0,13,13,13]: ... n = note.Note('G#') ... n.duration = duration.Duration('half') ... n.offset = x ... a.insert(n) ... >>> d = a.getOverlaps() >>> len(d[0]) 4 >>> len(d[13]) 3 >>> a = stream.Stream() >>> for x in [0,0,0,0,3,3,3]: ... n = note.Note('G#') ... n.duration = duration.Duration('whole') ... n.offset = x ... a.insert(n) ... >>> # default is to not include coincident boundaries >>> d = a.getOverlaps() >>> len(d[0]) 7
- getSimultaneous(includeDurationless=True)¶
Find and return any elements that start at the same time.
>>> from music21 import * >>> stream1 = stream.Stream() >>> for x in range(4): ... n = note.Note('G#') ... n.offset = x * 0 ... stream1.insert(n) ... >>> b = stream1.getSimultaneous() >>> len(b[0]) == 4 True >>> stream2 = stream.Stream() >>> for x in range(4): ... n = note.Note('G#') ... n.offset = x * 3 ... stream2.insert(n) ... >>> d = stream2.getSimultaneous() >>> len(d) == 0 True
- getTimeSignatures(searchContext=True, returnDefault=True, sortByCreationTime=True)¶
Collect all TimeSignature objects in this stream. If no TimeSignature objects are defined, get a default (4/4 or whatever is defined in the defaults.py file).
>>> from music21 import * >>> a = stream.Stream() >>> b = meter.TimeSignature('3/4') >>> a.insert(b) >>> a.repeatInsert(note.Note("C#"), range(10)) >>> c = a.getTimeSignatures() >>> len(c) == 1 True
- groupCount()¶
Get a dictionary for each groupId and the count of instances.
>>> from music21 import * >>> a = stream.Stream() >>> n = note.Note() >>> a.repeatAppend(n, 30) >>> a.addGroupForElements('P1') >>> a.groupCount() {'P1': 30} >>> a[12].groups.append('green') >>> a.groupCount() {'P1': 30, 'green': 1}
- groupElementsByOffset(returnDict=False)¶
Returns a List of lists in which each entry in the main list is a list of elements occurring at the same time. list is ordered by offset (since we need to sort the list anyhow in order to group the elements), so there is no need to call stream.sorted before running this.
if returnDict is True then it returns a dictionary of offsets and everything at that offset. If returnDict is False (default) then only a list of lists of elements grouped by offset is returned. (in other words, you’ll need to call list[i][0].getOffsetBySite(self) to get the offset)
>>> from music21 import * >>> s = stream.Stream() >>> s.insert(3, note.Note('C')) >>> s.insert(4, note.Note('C#')) >>> s.insert(4, note.Note('D-')) >>> s.insert(5, note.Note('D')) >>> returnList = s.groupElementsByOffset() >>> returnList [[<music21.note.Note C>], [<music21.note.Note C#>, <music21.note.Note D->], [<music21.note.Note D>]]>>> returnDict = s.groupElementsByOffset(returnDict = True) >>> returnDict {3.0: [<music21.note.Note C>], 4.0: [<music21.note.Note C#>, <music21.note.Note D->], 5.0: [<music21.note.Note D>]}Test that sorting still works...
>>> s.insert(0, meter.TimeSignature('2/4')) >>> s.insert(0, clef.TrebleClef()) # sorts first >>> s.groupElementsByOffset()[0] [<music21.clef.TrebleClef>, <music21.meter.TimeSignature 2/4>]it is DEFINITELY a feature that this method does not find elements within substreams that have the same absolute offset. See lily.translate for how this is useful for finding voices. For the other behavior, call Stream.flat first or Stream.recurse()
- hasElement(obj)¶
Return True if an element, provided as an argument, is contained in this Stream.
This method is based on object equivalence, not parameter equivalence of different objects.
>>> from music21 import * >>> s = stream.Stream() >>> n1 = note.Note('g') >>> n2 = note.Note('g#') >>> s.append(n1) >>> s.hasElement(n1) True
- hasElementByObjectId(objId)¶
Return True if an element object id, provided as an argument, is contained in this Stream.
>>> from music21 import * >>> s = stream.Stream() >>> n1 = note.Note('g') >>> n2 = note.Note('g#') >>> s.append(n1) >>> s.hasElementByObjectId(id(n1)) True >>> s.hasElementByObjectId(id(n2)) False
- hasElementOfClass(className, forceFlat=False)¶
Given a single class name as string, return True or False if an element with the specified class is found. Only a single class name can be given.
>>> from music21 import * >>> s = stream.Stream() >>> s.append(meter.TimeSignature('5/8')) >>> s.append(note.Note('d-2')) >>> s.insert(dynamics.Dynamic('fff')) >>> s.hasElementOfClass('TimeSignature') True >>> s.hasElementOfClass('Measure') False
- hasMeasures()¶
Return a boolean value showing if this Stream contains Measures.
>>> from music21 import * >>> s = stream.Stream() >>> s.repeatAppend(note.Note(), 8) >>> s.hasMeasures() False >>> s.makeMeasures(inPlace=True) >>> len(s.getElementsByClass('Measure')) 2 >>> s.hasMeasures() True
- hasPartLikeStreams()¶
Return a boolean value showing if this Stream contains multiple Parts, or Part-like sub-Streams. Part-like sub-streams are Streams that contain Measures or Notes.
>>> from music21 import * >>> s = stream.Score() >>> s.hasPartLikeStreams() False >>> p1 = stream.Part() >>> p1.repeatAppend(note.Note(), 8) >>> s.insert(0, p1) >>> s.hasPartLikeStreams() True
- hasVoices()¶
Return a boolean value showing if this Stream contains Voices
- haveAccidentalsBeenMade()¶
If Accidentals.displayStatus is None for all contained pitches, it as assumed that accidentals have not been set for display and/or makeAccidentals has not been run. If any Accidental has displayStatus other than None, this method returns True, regardless of if makeAccidentals has actually been run.
- haveBeamsBeenMade()¶
If any Note in this Stream has .beams defined, it as assumed that Beams have not been set and/or makeBeams has not been run. If any Beams exist, this method returns True, regardless of if makeBeams has actually been run.
- index(obj)¶
Return the first matched index for the specified object.
>>> from music21 import * >>> s = stream.Stream() >>> n1 = note.Note('g') >>> n2 = note.Note('g#') >>> s.insert(0, n1) >>> s.insert(5, n2) >>> len(s) 2 >>> s.index(n1) 0 >>> s.index(n2) 1
- insertAtNativeOffset(item)¶
Inserts an item at the offset that was defined before the item was inserted into a Stream.
That is item.getOffsetBySite(None); in fact, the entire code is self.insert(item.getOffsetBySite(None), item)
>>> from music21 import * >>> n1 = note.Note("F-") >>> n1.offset = 20.0 >>> stream1 = stream.Stream() >>> stream1.append(n1) >>> n1.getOffsetBySite(stream1) 0.0 >>> n1.offset 0.0 >>> stream2 = stream.Stream() >>> stream2.insertAtNativeOffset(n1) >>> stream2[0].offset 20.0 >>> n1.getOffsetBySite(stream2) 20.0
- insertIntoNoteOrChord(offset, noteOrChord)¶
Insert a Note or Chord into an offset position in this Stream. If there is another Note or Chord in this position, create a new Chord that combines the pitches of the inserted chord. If there is a Rest in this position, the Rest is replaced by the Note or Chord. The duration of the previously-found chord will remain the same in the new Chord.
- internalize(container=None, classFilterList=['GeneralNote'])¶
Gather all notes and related classes of this Stream and place inside a new container (like a Voice) in this Stream.
- invertDiatonic(inversionNote=<music21.note.Note C>, inPlace=True)¶
inverts a stream diatonically around the given note (by default, middle C)
For pieces where the key signature does not change throughout the piece it is MUCH faster than for pieces where the key signature changes.
Here in this test, we put Ciconia’s Quod Jactatur (a single voice piece that should have a canon solution: see trecento.quodJactatur) into 3 flats (instead of its original 1 flat) in measure 1, but into 5 sharps in measure 2 and then invert around F4, creating a new piece.
>>> from music21 import * >>> qj = corpus.parse('ciconia/quod_jactatur').parts[0] >>> qj.measures(1,2).show('text') {0.0} <music21.instrument.Instrument P1: MusicXML Part: Grand Piano> {0.0} <music21.stream.Measure 1 offset=0.0> {0.0} <music21.clef.Treble8vbClef> {0.0} <music21.key.KeySignature of 1 flat> {0.0} <music21.meter.TimeSignature 2/4> {0.0} <music21.layout.SystemLayout> {0.0} <music21.note.Note C> {1.5} <music21.note.Note D> {2.0} <music21.stream.Measure 2 offset=2.0> {0.0} <music21.note.Note E> {0.5} <music21.note.Note D> {1.0} <music21.note.Note C> {1.5} <music21.note.Note D> >>> k1 = qj.flat.getElementsByClass(key.KeySignature)[0] >>> qj.flat.replace(k1, key.KeySignature(-3)) >>> qj.getElementsByClass(stream.Measure)[1].insert(0, key.KeySignature(5)) >>> qj2 = qj.invertDiatonic(note.Note('F4'), inPlace = False) >>> qj2.measures(1,2).show('text') {0.0} <music21.instrument.Instrument P1: MusicXML Part: Grand Piano> {0.0} <music21.stream.Measure 1 offset=0.0> {0.0} <music21.clef.Treble8vbClef> {0.0} <music21.key.KeySignature of 3 flats> {0.0} <music21.meter.TimeSignature 2/4> {0.0} <music21.layout.SystemLayout> {0.0} <music21.note.Note B-> {1.5} <music21.note.Note A-> {2.0} <music21.stream.Measure 2 offset=2.0> {0.0} <music21.key.KeySignature of 5 sharps> {0.0} <music21.note.Note G#> {0.5} <music21.note.Note A#> {1.0} <music21.note.Note B> {1.5} <music21.note.Note A#>
- isSequence(includeDurationless=True, includeEndBoundary=False)¶
A stream is a sequence if it has no overlaps.
>>> from music21 import * >>> a = stream.Stream() >>> for x in [0,0,0,0,3,3,3]: ... n = note.Note('G#') ... n.duration = duration.Duration('whole') ... n.offset = x * 1 ... a.insert(n) ... >>> a.isSequence() False
- isTwelveTone()¶
Return true if this Stream only employs twelve-tone equal-tempered pitch values.
>>> from music21 import * >>> s = stream.Stream() >>> s.append(note.Note('G#4')) >>> s.isTwelveTone() True >>> s.append(note.Note('G~4')) >>> s.isTwelveTone() False
- isWellFormedNotation()¶
Return True if, given the context of this Stream or Stream subclass, contains what appears to be well-formed notation. This often means the formation of Measures, or a Score that contains Part with Measures.
>>> from music21 import * >>> s = corpus.parse('bwv66.6') >>> s.isWellFormedNotation() True >>> s.parts[0].isWellFormedNotation() True >>> s.parts[0].getElementsByClass('Measure')[0].isWellFormedNotation() True
- makeAccidentals(pitchPast=None, pitchPastMeasure=None, useKeySignature=True, alteredPitches=None, searchKeySignatureByContext=False, cautionaryPitchClass=True, cautionaryAll=False, inPlace=True, overrideStatus=False, cautionaryNotImmediateRepeat=True, lastNoteWasTied=False)¶
A method to set and provide accidentals given various conditions and contexts.
pitchPast is a list of pitches preceeding this pitch in this measure.
pitchPastMeasure is a list of pitches preceeding this pitch but in a previous measure.
If useKeySignature is True, a KeySignature will be searched for in this Stream or this Stream’s defined contexts. An alternative KeySignature can be supplied with this object and used for temporary pitch processing.
If alteredPitches is a list of modified pitches (Pitches with Accidentals) that can be directly supplied to Accidental processing. These are the same values obtained from a music21.key.KeySignature object using the alteredPitches property.
If cautionaryPitchClass is True, comparisons to past accidentals are made regardless of register. That is, if a past sharp is found two octaves above a present natural, a natural sign is still displayed.
If cautionaryAll is True, all accidentals are shown.
If overrideStatus is True, this method will ignore any current displayStatus stetting found on the Accidental. By default this does not happen. If displayStatus is set to None, the Accidental’s displayStatus is set.
If cautionaryNotImmediateRepeat is True, cautionary accidentals will be displayed for an altered pitch even if that pitch had already been displayed as altered.
If lastNoteWasTied is True, assume that the first note of the stream was tied to the previous note. TODO: make more robust for tied chords with only some pitches tied...
The updateAccidentalDisplay() method is used to determine if an accidental is necessary.
This will assume that the complete Stream is the context of evaluation. For smaller context ranges, call this on Measure objects.
If inPlace is True, this is done in-place; if inPlace is False, this returns a modified deep copy.
- makeBeams(inPlace=True)¶
Return a new Measure, or Stream of Measures, with beams applied to all notes. Measures with Voices will process voices independently.
In the process of making Beams, this method also updates tuplet types. This is destructive and thus changes an attribute of Durations in Notes.
Note that makeBeams() is automatically called in show(‘musicxml’) and other formats if there is no beaming information in the piece (see haveBeamsBeenMade)
If inPlace is True, this is done in-place; if inPlace is False, this returns a modified deep copy.
See getBeams() for the algorithm used.
>>> from music21 import * >>> aMeasure = stream.Measure() >>> aMeasure.timeSignature = meter.TimeSignature('4/4') >>> aNote = note.Note() >>> aNote.quarterLength = .25 >>> aMeasure.repeatAppend(aNote,16) >>> bMeasure = aMeasure.makeBeams()>>> for i in range(0, 4): ... print i, bMeasure.notes[i].beams 0 <music21.beam.Beams <music21.beam.Beam 1/start>/<music21.beam.Beam 2/start>> 1 <music21.beam.Beams <music21.beam.Beam 1/continue>/<music21.beam.Beam 2/stop>> 2 <music21.beam.Beams <music21.beam.Beam 1/continue>/<music21.beam.Beam 2/start>> 3 <music21.beam.Beams <music21.beam.Beam 1/stop>/<music21.beam.Beam 2/stop>>
- makeChords(minimumWindowSize=0.125, includePostWindow=True, removeRedundantPitches=True, useExactOffsets=False, gatherArticulations=True, gatherExpressions=True, inPlace=False, transferGroupsToPitches=False, makeRests=True)¶
Gathers simultaneously sounding Note objects into Chord objects, each of which contains all the pitches sounding together.
If useExactOffsets is True (default = False), then do an exact makeChords using the offsets in the piece. If this parameter is set, then minimumWindowSize is ignored.
This first example puts a part with three quarter notes (C4, D4, E4) together with a part consisting of a half note (C#5) and a quarter note (E#5) to make two Chords, the first containing the three Pitch objects sounding at the beginning, the second consisting of the two Pitches sounding on offset 2.0 (beat 3):
>>> from music21 import * >>> p1 = stream.Part() >>> p1.append([note.QuarterNote("C4"), note.QuarterNote("D4"), note.QuarterNote("E4"), note.QuarterNote("B2")]) >>> p2 = stream.Part() >>> p2.append([note.HalfNote("C#5"), note.QuarterNote("E#5"), chord.Chord(["E4","G5","C#7"])]) >>> sc1 = stream.Score() >>> sc1.insert(0, p1) >>> sc1.insert(0, p2) >>> scChords = sc1.flat.makeChords() >>> scChords.show('text') {0.0} <music21.chord.Chord C4 C#5 D4> {2.0} <music21.chord.Chord E4 E#5> {3.0} <music21.chord.Chord B2 E4 G5 C#7>The gathering of elements, starting from offset 0.0, uses the minimumWindowSize, in quarter lengths, to collect all Notes that start between 0.0 and the minimum window size (this permits overlaps within a minimum tolerance).
After collection, the maximum duration of collected elements is found; this duration is then used to set the new starting offset. A possible gap then results between the end of the window and offset specified by the maximum duration; these additional notes are gathered in a second pass if includePostWindow is True.
The new start offset is shifted to the larger of either the minimum window or the maximum duration found in the collected group. The process is repeated until all offsets are covered.
Each collection of Notes is formed into a Chord. The Chord is given the longest duration of all constituents, and is inserted at the start offset of the window from which it was gathered.
Chords can gather both articulations and expressions from found Notes using gatherArticulations and gatherExpressions.
If transferGroupsToPitches is True, and group defined on the source elements Groups object will be transfered to the Pitch objects conatained in the resulting Chord.
The resulting Stream, if not in-place, can also gather additional objects by placing class names in the collect list. By default, TimeSignature and KeySignature objects are collected.
- makeImmutable()¶
Clean this Stream: for self and all elements, purge all dead locations and remove all non-contained sites. Further, restore all active sites
- makeMeasures(meterStream=None, refStreamOrTimeRange=None, searchContext=False, innerBarline=None, finalBarline='final', bestClef=False, inPlace=False)¶
Takes a stream and places all of its elements into measures (Measure objects) based on the TimeSignature objects placed within the stream. If no TimeSignatures are found in the stream, a default of 4/4 is used.
If inPlace is True, the original Stream is modified and lost if inPlace is False, this returns a modified deep copy.
Many advanced features are provided:
(1) If a meterStream is provided, the TimeSignatures in this stream are used instead of any found in the Stream. Alternatively, a single TimeSignature object can be provided in lieu of the stream. This feature lets you test out how a group of notes might be interpreted as measures in a number of different metrical schemes.
(2) If refStreamOrTimeRange is provided, this Stream or List is used to give the span that you want to make measures for necessary to fill empty rests at the ends or beginnings of Streams, etc. Say for instance you’d like to make a complete score from a short ossia section, then you might use another Part from the Score as a refStreamOrTimeRange to make sure that the appropriate measures of rests are added at either side.
- If innerBarline is not None, the specified Barline object or string-specification of Barline style will be used to create Barline objects between every created Measure. The default is None.
- If finalBarline is not None, the specified Barline object or string-specification of Barline style will be used to create a Barline objects at the end of the last Measure. The default is ‘final’.
The searchContext parameter determines whether or not context searches are used to find Clef and other notation objects.
Here is a simple example of makeMeasures: a single measure of 4/4 is created by from a stream containing only three quarter notes:
>>> from music21 import * >>> sSrc = stream.Stream() >>> sSrc.append(note.QuarterNote('C4')) >>> sSrc.append(note.QuarterNote('D4')) >>> sSrc.append(note.QuarterNote('E4')) >>> sMeasures = sSrc.makeMeasures() >>> sMeasures.show('text') {0.0} <music21.stream.Measure 1 offset=0.0> {0.0} <music21.clef.TrebleClef> {0.0} <music21.meter.TimeSignature 4/4> {0.0} <music21.note.Note C> {1.0} <music21.note.Note D> {2.0} <music21.note.Note E> {3.0} <music21.bar.Barline style=final>Notice that the last measure is incomplete – makeMeasures does not fill up incomplete measures.
We can also check that the measure created has the correct TimeSignature:
>>> sMeasures[0].timeSignature <music21.meter.TimeSignature 4/4>Now let’s redo this work in 2/4 by putting a TimeSignature of 2/4 at the beginning of the stream and rerunning makeMeasures. Now we will have two measures, each with correct measure numbers:
>>> sSrc.insert(0.0, meter.TimeSignature('2/4')) >>> sMeasuresTwoFour = sSrc.makeMeasures() >>> sMeasuresTwoFour.show('text') {0.0} <music21.stream.Measure 1 offset=0.0> {0.0} <music21.meter.TimeSignature 2/4> {0.0} <music21.clef.TrebleClef> {0.0} <music21.note.Note C> {1.0} <music21.note.Note D> {2.0} <music21.stream.Measure 2 offset=2.0> {0.0} <music21.note.Note E> {1.0} <music21.bar.Barline style=final>Let us put 10 quarter notes in a Part. After we run makeMeasures, we will have 3 measures of 4/4 in a new Part object. This experiment demonstrates that running makeMeasures does not change the type of Stream you are using:
>>> sSrc = stream.Part() >>> n = note.Note('E-4') >>> n.quarterLength = 1 >>> sSrc.repeatAppend(n, 10) >>> sMeasures = sSrc.makeMeasures() >>> len(sMeasures.getElementsByClass('Measure')) 3 >>> sMeasures.__class__.__name__ 'Part'Demonstrate what makeMeasures will do with inPlace == True:
>>> sScr = stream.Stream() >>> sScr.insert(0, clef.TrebleClef()) >>> sScr.insert(0, meter.TimeSignature('3/4')) >>> sScr.append(note.Note('C4', quarterLength = 3.0)) >>> sScr.append(note.Note('D4', quarterLength = 3.0)) >>> sScr.makeMeasures(inPlace = True) >>> sScr.show('text') {0.0} <music21.stream.Measure 1 offset=0.0> {0.0} <music21.meter.TimeSignature 3/4> {0.0} <music21.clef.TrebleClef> {0.0} <music21.note.Note C> {3.0} <music21.stream.Measure 2 offset=3.0> {0.0} <music21.note.Note D> {3.0} <music21.bar.Barline style=final>If after running makeMeasures you run makeTies, it will also split long notes into smaller notes with ties. Lyrics and articulations are attached to the first note. Expressions (fermatas, etc.) will soon be attached to the last note but this is not yet done:
>>> p1 = stream.Part() >>> p1.append(meter.TimeSignature('3/4')) >>> longNote = note.Note("D#4") >>> longNote.quarterLength = 7.5 >>> longNote.articulations = [articulations.Staccato()] >>> longNote.lyric = "hi" >>> p1.append(longNote) >>> partWithMeasures = p1.makeMeasures() >>> dummy = partWithMeasures.makeTies(inPlace = True) >>> partWithMeasures.show('text') {0.0} <music21.stream.Measure 1 offset=0.0> {0.0} <music21.meter.TimeSignature 3/4> {0.0} <music21.clef.TrebleClef> {0.0} <music21.note.Note D#> {3.0} <music21.stream.Measure 2 offset=3.0> {0.0} <music21.note.Note D#> {6.0} <music21.stream.Measure 3 offset=6.0> {0.0} <music21.note.Note D#> {1.5} <music21.bar.Barline style=final> >>> allNotes = partWithMeasures.flat.notes >>> [allNotes[0].articulations, allNotes[1].articulations, allNotes[2].articulations] [[<music21.articulations.Staccato>], [], []] >>> [allNotes[0].lyric, allNotes[1].lyric, allNotes[2].lyric] ['hi', None, None]
- makeMutable(recurse=True)¶
No documentation.
- makeNotation(meterStream=None, refStreamOrTimeRange=None, inPlace=False, bestClef=False, **subroutineKeywords)¶
This method calls a sequence of Stream methods on this Stream to prepare notation, including creating voices for overlapped regions, Measures if necessary, creating ties, beams, and accidentals.
If inPlace is True, this is done in-place; if inPlace is False, this returns a modified deep copy.
makeAccidentalsKeywords can be a dict specifying additional parameters to send to makeAccidentals
>>> from music21 import * >>> s = stream.Stream() >>> n = note.Note('g') >>> n.quarterLength = 1.5 >>> s.repeatAppend(n, 10) >>> sMeasures = s.makeNotation() >>> len(sMeasures.getElementsByClass('Measure')) 4 >>> sMeasures.getElementsByClass('Measure')[-1].rightBarline.style 'final'
- makeRests(refStreamOrTimeRange=None, fillGaps=False, timeRangeFromBarDuration=False, inPlace=True)¶
Given a Stream with an offset not equal to zero, fill with one Rest preeceding this offset. This can be called on any Stream, a Measure alone, or a Measure that contains Voices.
If refStreamOrTimeRange is provided as a Stream, this Stream is used to get min and max offsets. If a list is provided, the list assumed to provide minimum and maximum offsets. Rests will be added to fill all time defined within refStream.
If fillGaps is True, this will create rests in any time regions that have no active elements.
If timeRangeFromBarDuration is True, and the calling Stream is a Measure with a TimeSignature, the time range will be determined based on the .barDuration property.
If inPlace is True, this is done in-place; if inPlace is False, this returns a modified deepcopy.
>>> from music21 import * >>> a = stream.Stream() >>> a.insert(20, note.Note()) >>> len(a) 1 >>> a.lowestOffset 20.0 >>> b = a.makeRests() >>> len(b) 2 >>> b.lowestOffset 0.0
- makeTies(meterStream=None, inPlace=True, displayTiedAccidentals=False)¶
Given a stream containing measures, examine each element in the Stream. If the elements duration extends beyond the measure’s boundary, create a tied entity, placing the split Note in the next Measure.
Note that this method assumes that there is appropriate space in the next Measure: this will not shift Note objects, but instead allocate them evenly over barlines. Generally, makeMeasures is called prior to calling this method.
If inPlace is True, this is done in-place; if inPlace is False, this returns a modified deep copy.
>>> from music21 import * >>> d = stream.Stream() >>> n = note.Note() >>> n.quarterLength = 12 >>> d.repeatAppend(n, 10) >>> d.repeatInsert(n, [x+.5 for x in range(10)]) >>> x = d.makeMeasures() >>> x = x.makeTies()
- makeTupletBrackets(inPlace=True)¶
Given a Stream of mixed durations, the first and last tuplet of any group of tuplets must be designated as the start and end.
Need to not only look at Notes, but components within Notes, as these might contain additional tuplets.
- makeVoices(inPlace=True, fillGaps=True)¶
If this Stream has overlapping Notes or Chords, this method will isolate all overlaps in unique Voices, and place those Voices in the Stream.
>>> from music21 import * >>> s = stream.Stream() >>> s.insert(0, note.Note('C4', quarterLength=4)) >>> s.repeatInsert(note.Note('b-4', quarterLength=.5), [x*.5 for x in range(0,8)]) >>> s.makeVoices(inPlace=True) >>> len(s.voices) 2 >>> [n.pitch for n in s.voices[0].notes] [C4] >>> [n.pitch for n in s.voices[1].notes] [B-4, B-4, B-4, B-4, B-4, B-4, B-4, B-4]
- measure(measureNumber, collect=['Clef', 'TimeSignature', 'Instrument', 'KeySignature'], searchContext=False)¶
Given a measure number, return a single Measure object if the Measure number exists, otherwise return None.
This method is distinguished from measures() in that this method returns a single Measure object, not a Stream containing one or more Measure objects.
>>> from music21 import * >>> a = corpus.parse('bach/bwv324.xml') >>> a.parts[0].measure(3) <music21.stream.Measure 3 offset=0.0>
- measureOffsetMap(classFilterList=None)¶
If this Stream contains Measures, provide a dictionary whose keys are the offsets of the start of each measure and whose values are a list of references to the Measure objects that start at that offset.
Even in normal music there may be more than one Measure starting at each offset because each Part might define its own Measure. However, you are unlikely to encounter such things unless you run Score.semiFlat, which retains all the containers found in the score.
The offsets are always measured relative to the calling Stream (self).
You can specify a classFilterList argument as a list of classes to find instead of Measures. But the default will of course find Measure objects.
Example 1: This Bach chorale is in 4/4 without a pickup, so as expected, measures are found every 4 offsets, until the weird recitation in m. 7 which in our edition lasts 10 beats and thus causes a gap in measureOffsetMap from 24.0 to 34.0.
>>> from music21 import * >>> chorale = corpus.parse('bach/bwv324.xml') >>> alto = chorale.parts['alto'] >>> altoMeasures = alto.measureOffsetMap() >>> sorted(altoMeasures.keys()) [0.0, 4.0, 8.0, 12.0, 16.0, 20.0, 24.0, 34.0, 38.0]altoMeasures is a dictionary (hash) of the measures that are found in the alto part, so we can get the measure beginning on offset 4.0 (measure 2) and display it (though it’s the only measure found at offset 4.0, there might be others as in example 2, so we need to call altoMeasures[4.0][0] to get this measure.):
>>> altoMeasures[4.0] [<music21.stream.Measure 2 offset=4.0>] >>> altoMeasures[4.0][0].show('text') {0.0} <music21.note.Note D> {1.0} <music21.note.Note D#> {2.0} <music21.note.Note E> {3.0} <music21.note.Note F#>Example 2: How to get all the measures from all parts (not the most efficient way, but it works!). Note that you first need to call semiFlat, which finds all containers (and other elements) nested inside all parts:
>>> choraleSemiFlat = chorale.semiFlat >>> choraleMeasures = choraleSemiFlat.measureOffsetMap() >>> choraleMeasures[4.0] [<music21.stream.Measure 2 offset=4.0>, <music21.stream.Measure 2 offset=4.0>, <music21.stream.Measure 2 offset=4.0>, <music21.stream.Measure 2 offset=4.0>]
- measureTemplate(fillWithRests=True)¶
If this Stream contains measures, return a new Stream with new Measures populated with the same characteristics of those found in this Stream.
- measures(numberStart, numberEnd, collect=['Clef', 'TimeSignature', 'Instrument', 'KeySignature'], gatherSpanners=True, searchContext=False)¶
Get a region of Measures based on a start and end Measure number, were the boundary numbers are both included. That is, a request for measures 4 through 10 will return 7 Measures, numbers 4 through 10.
Additionally, any number of associated classes can be gathered as well. Associated classes are the last found class relevant to this Stream or Part.
While all elements in the source are made available in the extracted region, new Measure objects are created and returned.
>>> from music21 import * >>> a = corpus.parse('bach/bwv324.xml') >>> b = a.parts[0].measures(4,6) >>> len(b.getElementsByClass('Measure')) 3
- melodicIntervals(*skipArgs, **skipKeywords)¶
Returns a Stream of Interval objects between Notes (and by default, Chords) that follow each other in a stream. the offset of the Interval is the offset of the beginning of the interval (if two notes are adjacent, then this offset is equal to the offset of the second note, but if skipRests is set to True or there is a gap in the Stream, then these two numbers will be different).
See findConsecutiveNotes() in this class for a discussion of what is meant by default for “consecutive notes”, and which keywords such as skipChords, skipRests, skipUnisons, etc. can be used to change that behavior.
The interval between a Note and a Chord (or between two chords) is the interval to the first pitch of the Chord (pitches[0]) which is usually the lowest. For more complex interval calculations, run findConsecutiveNotes() and then calculate your own intervals directly.
Returns an empty Stream if there are not at least two elements found by findConsecutiveNotes.
>>> from music21 import * >>> s1 = tinyNotation.TinyNotationStream("c4 d' r b b'", "3/4") >>> s1.show()
>>> intervalStream1 = s1.melodicIntervals() >>> intervalStream1.show('text') {1.0} <music21.interval.Interval M9> {4.0} <music21.interval.Interval P8>Using the skip attributes from findConsecutiveNotes(), we can alter which intervals are reported:
>>> intervalStream2 = s1.melodicIntervals(skipRests = True, skipOctaves=True) >>> intervalStream2.show('text') {1.0} <music21.interval.Interval M9> {2.0} <music21.interval.Interval m-3> >>> m3 = intervalStream2[1] >>> m3.directedNiceName 'Descending Minor Third'
- mergeElements(other, classFilterList=None)¶
Given another Stream, store references of each element in the other Stream in this Stream. This does not make copies of any elements, but simply stores all of them in this Stream.
Optionally, provide a list of classes to exclude with the classFilter list.
This method provides functionality like a shallow copy, but manages locations properly, only copies elements, and permits filtering by class type.
>>> from music21 import * >>> s1 = stream.Stream() >>> s2 = stream.Stream() >>> n1 = note.Note('f#') >>> n2 = note.Note('g') >>> s1.append(n1) >>> s1.append(n2) >>> s2.mergeElements(s1) >>> len(s2) 2 >>> s1[0] is s2[0] True >>> s1[1] is s2[1] True
- metronomeMarkBoundaries(srcObj=None)¶
Return a list of offset start, offset end, MetronomeMark triples for all TempoIndication objects found in this Stream or a Stream provided by srcObj.
If no MetronomeMarks are found, or an initial region does not have a MetronomeMark, a mark of quarter equal to 120 is provided as default.
Note that if other TempoIndication objets are defined, they will be converted to MetronomeMarks and returned here
>>> from music21 import * >>> s = stream.Stream() >>> s.repeatAppend(note.Note(), 8) >>> s.insert([6, tempo.MetronomeMark(number=240)]) >>> s.metronomeMarkBoundaries() [(0.0, 6.0, <music21.tempo.MetronomeMark animato Quarter=120>), (6.0, 8.0, <music21.tempo.MetronomeMark Quarter=240>)]
- pitchAttributeCount(pitchAttr='name')¶
Return a dictionary of pitch class usage (count) by selecting an attribute of the Pitch object.
>>> from music21 import corpus >>> a = corpus.parse('bach/bwv324.xml') >>> a.pitchAttributeCount('pitchClass') {0: 3, 2: 25, 3: 3, 4: 14, 6: 15, 7: 13, 9: 17, 11: 14} >>> a.pitchAttributeCount('name') {u'A': 17, u'C': 3, u'B': 14, u'E': 14, u'D': 25, u'G': 13, u'D#': 3, u'F#': 15} >>> a.pitchAttributeCount('nameWithOctave') {u'E3': 4, u'G4': 2, u'F#4': 2, u'A2': 2, u'E2': 1, u'G2': 1, u'D3': 9, u'D#3': 1, u'B4': 7, u'A3': 5, u'F#3': 13, u'A4': 10, u'B2': 3, u'B3': 4, u'C3': 2, u'E4': 9, u'D4': 14, u'D5': 2, u'D#4': 2, u'C5': 1, u'G3': 10}
- playingWhenAttacked(el, elStream=None)¶
Given an element (from another Stream) returns the single element in this Stream that is sounding while the given element starts.
If there are multiple elements sounding at the moment it is attacked, the method returns the first element of the same class as this element, if any. If no element is of the same class, then the first element encountered is returned. For more complex usages, use allPlayingWhileSounding.
Returns None if no elements fit the bill.
The optional elStream is the stream in which el is found. If provided, el’s offset in that Stream is used. Otherwise, the current offset in el is used. It is just in case you are paranoid that el.offset might not be what you want, because of some fancy manipulation of el.activeSite
>>> from music21 import * >>> n1 = note.Note("G#") >>> n2 = note.Note("D#") >>> s1 = stream.Stream() >>> s1.insert(20.0, n1) >>> s1.insert(21.0, n2) >>> n3 = note.Note("C#") >>> s2 = stream.Stream() >>> s2.insert(20.0, n3) >>> s1.playingWhenAttacked(n3).name 'G#' >>> n3.setOffsetBySite(s2, 20.5) >>> s1.playingWhenAttacked(n3).name 'G#' >>> n3.setOffsetBySite(s2, 21.0) >>> n3.offset 21.0 >>> s1.playingWhenAttacked(n3).name 'D#'Optionally, specify the site to get the offset from:
>>> n3.setOffsetBySite(None, 100) >>> n3.activeSite = None >>> s1.playingWhenAttacked(n3) >>> s1.playingWhenAttacked(n3, s2).name 'D#'
- plot(*args, **keywords)¶
Given a method and keyword configuration arguments, create and display a plot.
Note: plot() requires the Python package matplotib to be installed.
For details on arguments this function takes, see plotStream().
Available plots include the following Plot classes:
PlotHistogramPitchSpace PlotHistogramPitchClass PlotHistogramQuarterLength
PlotScatterPitchSpaceQuarterLength PlotScatterPitchClassQuarterLength PlotScatterPitchClassOffset PlotScatterPitchSpaceDynamicSymbol
PlotHorizontalBarPitchSpaceOffset PlotHorizontalBarPitchClassOffset
PlotScatterWeightedPitchSpaceQuarterLength PlotScatterWeightedPitchClassQuarterLength PlotScatterWeightedPitchSpaceDynamicSymbol
Plot3DBarsPitchSpaceQuarterLength
PlotWindowedKrumhanslSchmuckler PlotWindowedKrumhanslKessler PlotWindowedAardenEssen PlotWindowedSimpleWeights PlotWindowedBellmanBudge PlotWindowedTemperleyKostkaPayne PlotWindowedAmbitus
>>> from music21 import * >>> s = corpus.parse('bach/bwv57.8') >>> s.plot('pianoroll')![]()
- pop(index)¶
Return and remove the object found at the user-specified index value. Index values are those found in elements and are not necessary offset order.
>>> from music21 import * >>> a = stream.Stream() >>> a.repeatInsert(note.Note("C"), range(10)) >>> junk = a.pop(0) >>> len(a) 9
- quantize(quarterLengthDivisors=[4, 3], processOffsets=True, processDurations=True, inPlace=False, recurse=True)¶
Quantize time values in this Stream by snapping offsets and/or durations to the nearest multiple of a quarter length value given as one or more divisors of 1 quarter length. The quantized value found closest to a divisor multiple will be used.
The quarterLengthDivisors provides a flexible way to provide quantization settings. For example, [2] will snap all events to eighth note grid. [4, 3] will snap events to sixteenth notes and eighth note triplets, whichever is closer. [4, 6] will snap events to sixteenth notes and sixteenth note triplets.
processOffsets determines whether the Offsets are quantized.
processDurations determines whether the Durations are quantized.
Both are set to True by default. Setting both to False does nothing to the Stream.
if inPlace is True then the quantization is done on the Stream itself. If False (default) then a new quantized Stream of the same class is returned.
If recurse is True then all substreams are also quantized. If False (default) then only the highest level of the Stream is quantized.
>>> from music21 import * >>> n = note.Note() >>> n.quarterLength = .49 >>> s = stream.Stream() >>> s.repeatInsert(n, [0.1, .49, .9]) >>> nshort = note.Note() >>> nshort.quarterLength = .26 >>> s.repeatInsert(nshort, [1.49, 1.76]) >>> s.quantize([4], processOffsets=True, processDurations=True, inPlace=True) >>> [e.offset for e in s] [0.0, 0.5, 1.0, 1.5, 1.75] >>> [e.duration.quarterLength for e in s] [0.5, 0.5, 0.5, 0.25, 0.25]TODO: test recurse and inPlace etc.
- realizeOrnaments()¶
Realize all ornaments on a stream
Creates a new stream that contains all realized ornaments in addition to other elements in the original stream.
>>> from music21 import * >>> s1 = stream.Stream() >>> m1 = stream.Measure() >>> m1.timeSignature = meter.TimeSignature("4/4") >>> n1 = note.WholeNote("C4") >>> n1.expressions.append(expressions.Mordent()) >>> m1.append(n1) >>> m2 = stream.Measure() >>> n2 = note.WholeNote("D4") >>> m2.append(n2) >>> s1.append(m1) >>> s1.append(m2) >>> s1.recurse() [<music21.stream.Stream ...>, <music21.stream.Measure 0 offset=0.0>, <music21.meter.TimeSignature 4/4>, <music21.note.Note C>, <music21.stream.Measure 0 offset=4.0>, <music21.note.Note D>] >>> s2 = s1.realizeOrnaments() >>> s2.recurse() [<music21.stream.Stream ...>, <music21.stream.Measure 0 offset=0.0>, <music21.meter.TimeSignature 4/4>, <music21.note.Note C>, <music21.note.Note B>, <music21.note.Note C>, <music21.stream.Measure 0 offset=4.0>, <music21.note.Note D>]
- recurse(direction='downward', streamsOnly=False, restoreActiveSites=True, skipDuplicates=True, classFilter=[])¶
Iterate over a list of all Music21Objects contained in the Stream, starting with self, continuing with self’s elements, and whenever finding a Stream subclass in self, that Stream subclass’s elements.
TODO: WRITE DOCS AND TESTS ETC.!!!!
- remove(targetOrList, firstMatchOnly=True, shiftOffsets=False)¶
Remove an object from this Stream. Additionally, this Stream is removed from the object’s sites in DefinedContexts.
By default, only the first match is removed. This can be adjusted with the firstMatchOnly parameters. If a list of objects is passed, they will all be removed. If shiftOffsets is True, then offsets will be corrected after object removal. It is more efficient to pass a list of objects than to call remove on each object individually if shiftOffsets is True.
>>> from music21 import * >>> s = stream.Stream() >>> n1 = note.Note('g') >>> n2 = note.Note('g#') >>> # copies of an object are not the same as the object >>> n3 = copy.deepcopy(n2) >>> s.insert(10, n1) >>> s.insert(5, n2) >>> s.remove(n1) >>> len(s) 1 >>> s.insert(20, n3) >>> s.remove(n3) >>> [e for e in s] == [n2] TrueNo error is raised if the target is not found.
>>> s.remove(n3) >>> s2 = stream.Stream() >>> c = clef.TrebleClef() >>> n1, n2, n3, n4 = note.Note('a'), note.Note('b'), note.Note('c'), note.Note('d') >>> n5, n6, n7, n8 = note.Note('e'), note.Note('f'), note.Note('g'), note.Note('a') >>> s2.insert(0.0, c) >>> s2.append([n1,n2,n3,n4,n5,n6,n7,n8]) >>> s2.remove(n1, shiftOffsets = True) >>> s2.show('text') {0.0} <music21.clef.TrebleClef> {0.0} <music21.note.Note B> {1.0} <music21.note.Note C> {2.0} <music21.note.Note D> {3.0} <music21.note.Note E> {4.0} <music21.note.Note F> {5.0} <music21.note.Note G> {6.0} <music21.note.Note A>>>> s2.remove([n3, n6, n4], shiftOffsets = True) >>> s2.show('text') {0.0} <music21.clef.TrebleClef> {0.0} <music21.note.Note B> {1.0} <music21.note.Note E> {2.0} <music21.note.Note G> {3.0} <music21.note.Note A>
- removeByClass(classFilterList)¶
Remove all elements from the Stream based on one or more classes given in a list.
>>> from music21 import * >>> s = stream.Stream() >>> s.append(meter.TimeSignature('4/4')) >>> s.repeatAppend(note.Note("C"), 8) >>> len(s) 9 >>> s.removeByClass('GeneralNote') >>> len(s) 1 >>> len(s.notes) 0
- removeByNotOfClass(classFilterList)¶
Remove all elements not of the specified class or subclass in the Steam in place.
- repeatAppend(item, numberOfTimes)¶
Given an object and a number, run append that many times on a deepcopy of the object. numberOfTimes should of course be a positive integer.
>>> from music21 import * >>> a = stream.Stream() >>> n = note.Note('D--') >>> n.duration.type = "whole" >>> a.repeatAppend(n, 10) >>> a.show('text') {0.0} <music21.note.Note D--> {4.0} <music21.note.Note D--> {8.0} <music21.note.Note D--> {12.0} <music21.note.Note D--> ... {36.0} <music21.note.Note D-->>>> a.duration.quarterLength 40.0 >>> a[9].offset 36.0
- repeatInsert(item, offsets)¶
Given an object, create a deep copy of each object at each positions specified by the offset list:
>>> from music21 import * >>> a = stream.Stream() >>> n = note.Note('G-') >>> n.quarterLength = 1>>> a.repeatInsert(n, [0, 2, 3, 4, 4.5, 5, 6, 7, 8, 9, 10, 11, 12]) >>> len(a) 13 >>> a[10].offset 10.0
- replace(target, replacement, firstMatchOnly=False, allTargetSites=True)¶
Given a target object, replace all references of that object with references to the supplied replacement object.
If allTargetSites is True (as it is by default), all sites that have a reference for the replacement will be similarly changed. This is useful for altering both a flat and nested representation.
- restoreActiveSites()¶
Restore all active sites for all elements from this Stream downward.
- setDerivation(target)¶
Manually set the Stream that this Stream was derived from. This operation is generally completed automatically.
See Derivation for more information.
- setupSerializationScaffold(topLevel=True, streamIdsFound=None)¶
Prepare this stream and all of its contents for pickle/pickling, that is, serializing and storing an object representation on file or as a string.
The topLevel and streamIdsFound arguments are used to keep track of recursive calls.
Note that this is a destructive process: elements contained within this Stream will have their sites cleared of all contents not in the hierarchy of the Streams. Thus, a deepcopy of the Stream may be necessary before calling this method.
>>> from music21 import * >>> a = stream.Stream() >>> n = note.Note() >>> n.duration.type = "whole" >>> a.repeatAppend(n, 10) >>> a.setupSerializationScaffold()
- shiftElements(offset, classFilterList=None)¶
Add the given offset value to every offset of the objects found in the Stream. Objects that are specifically placed at the end of the Stream via .storeAtEnd() (such as right barlines) are not affected.
>>> from music21 import * >>> a = stream.Stream() >>> a.repeatInsert(note.Note("C"), range(0,10)) >>> a.shiftElements(30) >>> a.lowestOffset 30.0 >>> a.shiftElements(-10) >>> a.lowestOffset 20.0
- showVariantAsOssialikePart(containedPart, variantGroups, inPlace=False)¶
Takes a part within the score and a variant within that part. Puts the variant object in a part surrounded by hidden rests to mimic the appearence of an ossia despite limited musicXML support for ossia staves. Note that this will ignore variants with .lengthType ‘elongation’ and ‘deletion’ as there is no good way to represent ossia staves like those by this method.
>>> from music21 import * >>> sPartStream = converter.parse(" d4 e4 f4 g4 a2 b-4 a4 g4 a8 g8 f4 e4 d2 a2 d4 e4 f4 g4 a2 b-4 a4 g4 a8 b-8 c'4 c4 f1", "4/4") >>> sPartStream.makeMeasures(inPlace = True) >>> v1stream = converter.parse(" a2. b-8 a8", "4/4") >>> v2stream = converter.parse(" d4 f4 a2", "4/4") >>> v1 = variant.Variant() >>> v1measure = stream.Measure() >>> v1.insert(0.0, v1measure) >>> for e in v1stream.notesAndRests: ... v1measure.insert(e.offset, e)>>> v2 = variant.Variant() >>> v2measure = stream.Measure() >>> v2.insert(0.0, v2measure) >>> for e in v2stream.notesAndRests: ... v2measure.insert(e.offset, e) >>> v3 = variant.Variant() >>> v2.replacementDuration = 4.0 >>> v3.replacementDuration = 4.0 >>> v1.groups = ["variant1"] >>> v2.groups = ["variant2"] >>> v3.groups = ["variant3"]>>> sPart = stream.Part() >>> for e in sPartStream: ... sPart.insert(e.offset, e) >>> sPart.insert(4.0, v1) >>> sPart.insert(12.0, v2) >>> sPart.insert(20.0, v3) #This is a deletion variant and will be skipped >>> s = stream.Score() >>> s.insert(0.0, sPart) >>> streamWithOssia = s.showVariantAsOssialikePart(sPart, ['variant1', 'variant2', 'variant3'], inPlace = False) >>> streamWithOssia.show()
- simultaneousAttacks(stream2)¶
returns an ordered list of offsets where elements are started (attacked) at the same time in both self and stream2.
In this example, we create one stream of Qtr, Half, Qtr, and one of Half, Qtr, Qtr. There are simultaneous attacks at offset 0.0 (the beginning) and at offset 3.0, but not at 1.0 or 2.0:
>>> from music21 import * >>> st1 = stream.Stream() >>> st2 = stream.Stream() >>> st1.append([note.QuarterNote(), note.HalfNote(), note.QuarterNote()]) >>> st2.append([note.HalfNote(), note.QuarterNote(), note.QuarterNote()]) >>> print st1.simultaneousAttacks(st2) [0.0, 3.0]
- sliceAtOffsets(offsetList, target=None, addTies=True, inPlace=False, displayTiedAccidentals=False)¶
Given a list of quarter lengths, slice and optionally tie all Durations at these points.
>>> from music21 import * >>> s = stream.Stream() >>> n = note.Note() >>> n.quarterLength = 4 >>> s.append(n) >>> post = s.sliceAtOffsets([1, 2, 3], inPlace=True) >>> [(e.offset, e.quarterLength) for e in s] [(0.0, 1.0), (1.0, 1.0), (2.0, 1.0), (3.0, 1.0)]
- sliceByBeat(target=None, addTies=True, inPlace=False, displayTiedAccidentals=False)¶
Slice all elements in the Stream that have a Duration at the offsets determined to be the beat from the local TimeSignature.
- sliceByGreatestDivisor(addTies=True, inPlace=False)¶
Slice all Duration objects on all Notes of this Stream. Duration are sliced according to the approximate GCD found in all durations.
- sliceByQuarterLengths(quarterLengthList, target=None, addTies=True, inPlace=False)¶
Slice all Duration objects on all Notes of this Stream. Duration are sliced according to values provided in quarterLengthList list. If the sum of these values is less than the Duration, the values are accumulated in a loop to try to fill the Duration. If a match cannot be found, an Exception is raised.
If target == None, the entire Stream is processed. Otherwise, only the element specified is manipulated.
- sort(force=False)¶
Sort this Stream in place by offset, then priority, then standard class sort order (e.g., Clefs before KeySignatures before TimeSignatures).
Note that Streams automatically sort themsevlves unless autoSort is set to False (as in the example below)
If force is True, a sort will be attempted regardless of any other parameters.
>>> from music21 import * >>> n1 = note.Note('a') >>> n2 = note.Note('b') >>> s = stream.Stream() >>> s.autoSort = False >>> s.insert(100, n2) >>> s.insert(0, n1) # now a has a lower offset by higher index >>> [n.name for n in s] ['B', 'A'] >>> s.sort() >>> [n.name for n in s] ['A', 'B']
- splitAtQuarterLength(quarterLength, retainOrigin=True, addTies=True, displayTiedAccidentals=False, searchContext=True, delta=1e-06)¶
This method overrides the method on Music21Object to provide similar functionality for Streams. Most arguments are passed to Music21Object.splitAtQuarterLength.
- splitByClass(classObj, fx)¶
Given a stream, get all objects of type classObj and divide them into two new streams depending on the results of fx. Fx should be a lambda or other function on elements. All elements where fx returns True go in the first stream. All other elements are put in the second stream.
If classObj is None then all elements are returned. ClassObj can also be a list of classes.
In this example, we will create 50 notes from midi note 30 (two octaves and a tritone below middle C) to midi note 80 (an octave and a minor sixth above middle C) and add them to a Stream. We then create a lambda function to split between those notes below middle C (midi note 60) and those above (google “lambda functions in Python” for more information on what these powerful tools are).
>>> from music21 import * >>> stream1 = stream.Stream() >>> for x in range(30,81): ... n = note.Note() ... n.midi = x ... stream1.append(n) >>> fx = lambda n: n.midi < 60 >>> b, c = stream1.splitByClass(note.Note, fx)Stream b now contains all the notes below middle C, that is, 30 notes, beginning with F#1 and ending with B3 while Stream c has the 21 notes from C4 to A-5:
>>> len(b) 30 >>> (b[0].nameWithOctave, b[-1].nameWithOctave) ('F#1', 'B3') >>> len(c) 21 >>> (c[0].nameWithOctave, c[-1].nameWithOctave) ('C4', 'G#5')
- storeAtEnd(itemOrList, ignoreSort=False)¶
Inserts an item or items at the end of the Stream, stored in the special box (called _endElements).
This method is useful for putting things such as right bar lines or courtesy clefs that should always be at the end of a Stream no matter what else is appended to it
As sorting is done only by priority and class, it cannot avoid setting isSorted to False.
- stripTies(inPlace=False, matchByPitch=False, retainContainers=False)¶
Find all notes that are tied; remove all tied notes, then make the first of the tied notes have a duration equal to that of all tied constituents. Lastly, remove the formerly-tied notes.
This method can be used on Stream and Stream subclasses. When used on a Score, Parts and Measures are retained.
If retainContainers is False (by default), this method only returns Note objects; Measures and other structures are stripped from the Stream. Set retainContainers to True to remove ties from a Part Stream that contains Measure Streams, and get back a multi-Measure structure.
Presently, this only works if tied notes are sequentual; ultimately this will need to look at .to and .from attributes (if they exist)
In some cases (under makeMeasures()) a continuation note will not have a Tie object with a stop attribute set. In that case, we need to look for sequential notes with matching pitches. The matchByPitch option can be used to use this technique.
>>> from music21 import * >>> a = stream.Stream() >>> n = note.Note() >>> n.quarterLength = 6 >>> a.append(n) >>> m = a.makeMeasures() >>> m.makeTies() >>> len(m.flat.notes) 2 >>> m = m.stripTies() >>> len(m.flat.notes) 1
- teardownSerializationScaffold()¶
After rebuilding this stream from pickled storage, prepare this as a normal Stream.
>>> from music21 import * >>> a = stream.Stream() >>> n = note.Note() >>> n.duration.type = "whole" >>> a.repeatAppend(n, 10) >>> a.setupSerializationScaffold() >>> a.teardownSerializationScaffold()
- toSoundingPitch(inPlace=True)¶
If not at sounding pitch, transpose all Pitch elements to sounding pitch. The atSoundingPitch property is used to determine if transposition is necessary.
- toWrittenPitch(inPlace=True)¶
If not at written pitch, transpose all Pitch elements to written pitch. The atSoundingPitch property is used to determine if transposition is necessary.
- transferOffsetToElements()¶
Transfer the offset of this stream to all internal elements; then set the offset of this stream to zero.
>>> from music21 import * >>> a = stream.Stream() >>> a.repeatInsert(note.Note("C"), range(0,10)) >>> a.offset = 30 >>> a.transferOffsetToElements() >>> a.lowestOffset 30.0 >>> a.offset 0.0 >>> a.offset = 20 >>> a.transferOffsetToElements() >>> a.lowestOffset 50.0
- trimPlayingWhileSounding(el, elStream=None, requireClass=False, padStream=False)¶
Returns a Stream of deepcopies of elements in otherStream that sound at the same time as`el. but with any element that was sounding when el. begins trimmed to begin with el. and any element sounding when el ends trimmed to end with el.
if padStream is set to true then empty space at the beginning and end is filled with a generic Music21Object, so that no matter what otherStream is the same length as el.
Otherwise is the same as allPlayingWhileSounding – but because these elements are deepcopies, the difference might bite you if you’re not careful.
Note that you can make el an empty stream of offset X and duration Y to extract exactly that much information from otherStream.
- unwrapWeakref()¶
Overridden method for unwrapping all Weakrefs.
- voicesToParts()¶
If this Stream defines one or more voices, extract each into a Part, returning a Score.
If this Stream has no voice, return the Stream as a Part within a Score.
- wrapWeakref()¶
Overridden method for unwrapping all Weakrefs.
Methods inherited from Music21Object: addContext(), addLocation(), addLocationAndActiveSite(), freezeIds(), getAllContextsByClass(), getCommonSiteIds(), getCommonSites(), getContextAttr(), getContextByClass(), getOffsetBySite(), getSiteIds(), getSites(), getSpannerSites(), hasContext(), hasSite(), hasSpannerSite(), hasVariantSite(), isClassOrSubclass(), mergeAttributes(), next(), previous(), purgeLocations(), purgeOrphans(), purgeUndeclaredIds(), removeLocationBySite(), removeLocationBySiteId(), searchActiveSiteByAttr(), setContextAttr(), setOffsetBySite(), show(), splitAtDurations(), splitByQuarterLengths(), unfreezeIds(), write()
Methods inherited from JSONSerializer: jsonAttributes(), jsonComponentFactory(), jsonPrint(), jsonRead(), jsonWrite()
Inherits from: Stream, Music21Object, JSONSerializer
A representation of a Measure organized as a Stream.
All properties of a Measure that are Music21 objects are found as part of the Stream’s elements.
Measure attributes
- number¶
A number representing the displayed or shown Measure number as presented in a written Score.
- timeSignatureIsNew¶
Boolean describing if the TimeSignature is different than the previous Measure.
- layoutWidth¶
A suggestion for layout width, though most rendering systems do not support this designation. Use SystemLayout objects instead.
- clefIsNew¶
Boolean describing if the Clef is different than the previous Measure.
- keyIsNew¶
Boolean describing if KeySignature is different than the previous Measure.
- numberSuffix¶
If a Measure number has a string annotation, such as “a” or similar, this string is stored here.
Attributes without Documentation: isMeasure, filled, paddingRight, paddingLeft
Attributes inherited from Stream: isStream, isFlat, autoSort, isSorted, flattenedRepresentationOf
Attributes inherited from Music21Object: classSortOrder, isSpanner, isVariant, id, groups, hideObjectOnPrint
Measure properties
- barDuration¶
Return the bar duration, or the Duration specified by the TimeSignature, regardless of what elements are found in this Measure or the highest time. TimeSignature is found first within the Measure, or within a context based search.
- clef¶
>>> from music21 import * >>> a = stream.Measure() >>> a.clef = clef.TrebleClef() >>> a.clef.sign # clef is an element 'G'
- keySignature¶
>>> from music21 import * >>> a = stream.Measure() >>> a.keySignature = key.KeySignature(0) >>> a.keySignature.sharps 0
- leftBarline¶
Get or set the left barline, or the Barline object found at offset zero of the Measure. Can be set either with a string representing barline style or a bar.Barline() object or None. Note that not all bars have barline objects here – regular barlines don’t need them.
- musicxml¶
Provide a complete MusicXML representation of the measure.
- mx¶
Return a music21.musicxml.Measure object, populated with notes, chords, rests and a music21.musixcml.Attributes object, populated with time, meter, key, etc
Not needed for most users. Call myMeasure.show(‘musicxml’) or myMeasure.write(‘musicxml’) instead.
>>> from music21 import * >>> a = note.Note() >>> a.quarterLength = 4 >>> b = stream.Measure() >>> b.insert(0, a) >>> len(b) 1 >>> mxMeasure = b.mx >>> len(mxMeasure) 1
- rightBarline¶
Get or set the right barline, or the Barline object found at the offset equal to the bar duration.
>>> from music21 import * >>> b = bar.Barline('final') >>> m = stream.Measure() >>> print m.rightBarline None >>> m.rightBarline = b >>> m.rightBarline.style 'final'
- timeSignature¶
>>> from music21 import * >>> a = stream.Measure() >>> a.timeSignature = meter.TimeSignature('2/4') >>> a.timeSignature.numerator, a.timeSignature.denominator (2, 4)Properties inherited from Stream: atSoundingPitch, beat, beatDuration, beatStr, beatStrength, derivationChain, derivationMethod, derivesFrom, duration, elements, finalBarline, flat, highestOffset, highestTime, isGapless, lowestOffset, metadata, midiFile, notes, notesAndRests, offsetMap, pitches, rootDerivation, seconds, secondsMap, semiFlat, sorted, spannerBundle, spanners, variants, voices
Properties inherited from Music21Object: activeSite, classes, derivationHierarchy, isGrace, measureNumber, offset, priority
Properties inherited from JSONSerializer: json
Measure methods
- addRepeat()¶
No documentation.
- addTimeDependentDirection(time, direction)¶
No documentation.
- barDurationProportion(barDuration=None)¶
Return a floating point value greater than 0 showing the proportion of the bar duration that is filled based on the highest time of all elements. 0.0 is empty, 1.0 is filled; 1.5 specifies of an overflow of half.
Bar duration refers to the duration of the Measure as suggested by the TimeSignature. This value cannot be determined without a Time Signature.
An already-obtained Duration object can be supplied with the barDuration optional argument.
>>> from music21 import * >>> m = stream.Measure() >>> m.timeSignature = meter.TimeSignature('3/4') >>> n = note.Note() >>> n.quarterLength = 1 >>> m.append(copy.deepcopy(n)) >>> m.barDurationProportion() 0.33333... >>> m.append(copy.deepcopy(n)) >>> m.barDurationProportion() 0.66666... >>> m.append(copy.deepcopy(n)) >>> m.barDurationProportion() 1.0 >>> m.append(copy.deepcopy(n)) >>> m.barDurationProportion() 1.33333...
- bestTimeSignature()¶
Given a Measure with elements in it, get a TimeSignature that contains all elements.
Note: this does not yet accommodate triplets.
- makeNotation(inPlace=False)¶
This method calls a sequence of Stream methods on this Measure to prepare notation.
If inPlace is True, this is done in-place; if inPlace is False, this returns a modified deep copy.
>>> from music21 import * >>> m = stream.Measure() >>> n1 = note.Note('g#') >>> n2 = note.Note('g') >>> m.append([n1, n2]) >>> m.makeNotation(inPlace=True) >>> m.notes[1].pitch.accidental <accidental natural>
- measureNumberWithSuffix()¶
No documentation.
- mergeAttributes(other)¶
Given another Measure, configure all non-element attributes of this Measure with the attributes of the other Measure. No elements will be changed or copied.
This method is necessary because Measures, unlike some Streams, have attributes independent of any stored elements.
- padAsAnacrusis()¶
Given an incompletely filled Measure, adjust the paddingLeft value to to represent contained events as shifted to fill the right-most duration of the bar.
Calling this method will overwrite any previously set paddingLeft value, based on the current TimeSignature-derived barDuration attribute.
>>> from music21 import * >>> m = stream.Measure() >>> m.timeSignature = meter.TimeSignature('3/4') >>> n = note.Note() >>> n.quarterLength = 1 >>> m.append(copy.deepcopy(n)) >>> m.padAsAnacrusis() >>> m.paddingLeft 2.0 >>> m.timeSignature = meter.TimeSignature('5/4') >>> m.padAsAnacrusis() >>> m.paddingLeft 4.0Methods inherited from Stream: activateVariants(), addGroupForElements(), allPlayingWhileSounding(), analyze(), append(), attachIntervalsBetweenStreams(), attachMelodicIntervals(), attributeCount(), augmentOrDiminish(), bestClef(), chordify(), expandRepeats(), explode(), extendDuration(), extendDurationAndGetBoundaries(), extendTies(), extractContext(), findConsecutiveNotes(), findGaps(), flattenUnnecessaryVoices(), getClefs(), getElementAfterElement(), getElementAfterOffset(), getElementAtOrAfter(), getElementAtOrBefore(), getElementBeforeElement(), getElementBeforeOffset(), getElementById(), getElementByObjectId(), getElementsByClass(), getElementsByGroup(), getElementsByOffset(), getElementsNotOfClass(), getInstrument(), getInstruments(), getKeySignatures(), getOffsetByElement(), getOverlaps(), getSimultaneous(), getTimeSignatures(), groupCount(), groupElementsByOffset(), hasElement(), hasElementByObjectId(), hasElementOfClass(), hasMeasures(), hasPartLikeStreams(), hasVoices(), haveAccidentalsBeenMade(), haveBeamsBeenMade(), index(), insert(), insertAndShift(), insertAtNativeOffset(), insertIntoNoteOrChord(), internalize(), invertDiatonic(), isSequence(), isTwelveTone(), isWellFormedNotation(), makeAccidentals(), makeBeams(), makeChords(), makeImmutable(), makeMeasures(), makeMutable(), makeRests(), makeTies(), makeTupletBrackets(), makeVoices(), measure(), measureOffsetMap(), measureTemplate(), measures(), melodicIntervals(), mergeElements(), metronomeMarkBoundaries(), pitchAttributeCount(), playingWhenAttacked(), plot(), pop(), quantize(), realizeOrnaments(), recurse(), remove(), removeByClass(), removeByNotOfClass(), repeatAppend(), repeatInsert(), replace(), restoreActiveSites(), scaleDurations(), scaleOffsets(), setDerivation(), setupSerializationScaffold(), shiftElements(), showVariantAsOssialikePart(), simultaneousAttacks(), sliceAtOffsets(), sliceByBeat(), sliceByGreatestDivisor(), sliceByQuarterLengths(), sort(), splitAtQuarterLength(), splitByClass(), storeAtEnd(), stripTies(), teardownSerializationScaffold(), toSoundingPitch(), toWrittenPitch(), transferOffsetToElements(), transpose(), trimPlayingWhileSounding(), unwrapWeakref(), voicesToParts(), wrapWeakref()
Methods inherited from Music21Object: addContext(), addLocation(), addLocationAndActiveSite(), freezeIds(), getAllContextsByClass(), getCommonSiteIds(), getCommonSites(), getContextAttr(), getContextByClass(), getOffsetBySite(), getSiteIds(), getSites(), getSpannerSites(), hasContext(), hasSite(), hasSpannerSite(), hasVariantSite(), isClassOrSubclass(), next(), previous(), purgeLocations(), purgeOrphans(), purgeUndeclaredIds(), removeLocationBySite(), removeLocationBySiteId(), searchActiveSiteByAttr(), setContextAttr(), setOffsetBySite(), show(), splitAtDurations(), splitByQuarterLengths(), unfreezeIds(), write()
Methods inherited from JSONSerializer: jsonAttributes(), jsonComponentFactory(), jsonPrint(), jsonRead(), jsonWrite()
Inherits from: Stream, Music21Object, JSONSerializer
A Stream subclass for handling multi-work music encodings. Many ABC files, for example, define multiple works or parts within a single file.
Opus attributes
Attributes inherited from Stream: isMeasure, isStream, isFlat, autoSort, isSorted, flattenedRepresentationOf
Attributes inherited from Music21Object: classSortOrder, isSpanner, isVariant, id, groups, hideObjectOnPrint
Opus properties
Properties inherited from Stream: notes, pitches, atSoundingPitch, beat, beatDuration, beatStr, beatStrength, derivationChain, derivationMethod, derivesFrom, duration, elements, finalBarline, flat, highestOffset, highestTime, isGapless, lowestOffset, metadata, midiFile, musicxml, mx, notesAndRests, offsetMap, rootDerivation, seconds, secondsMap, semiFlat, sorted, spannerBundle, spanners, variants, voices
Properties inherited from Music21Object: activeSite, classes, derivationHierarchy, isGrace, measureNumber, offset, priority
Properties inherited from JSONSerializer: json
Opus methods
- getNumbers()¶
Return a list of all numbers defined in this Opus.
>>> from music21 import * >>> o = corpus.parse('josquin/ovenusbant') >>> o.getNumbers() ['1', '2', '3']
- getScoreByNumber(opusMatch)¶
Get Score objects from this Stream by number. Performs title search using the search() method, and returns the first result.
>>> from music21 import * >>> o = corpus.parse('josquin/ovenusbant') >>> o.getNumbers() ['1', '2', '3'] >>> s = o.getScoreByNumber(2) >>> s.metadata.title 'O Venus bant' >>> s.metadata.alternativeTitle 'Tenor'
- getScoreByTitle(titleMatch)¶
Get Score objects from this Stream by a title. Performs title search using the search() method, and returns the first result.
>>> from music21 import * >>> o = corpus.parse('essenFolksong/erk5') >>> s = o.getScoreByTitle('Vrienden, kommt alle gaere') >>> s = o.getScoreByTitle('(.*)kommt(.*)') # regular expression >>> s.metadata.title 'Vrienden, kommt alle gaere'
- mergeScores()¶
Some Opus object represent numerous scores that are individual parts of the same work. This method will treat each contained Score as a Part, merging and returning a single Score with merged Metadata.
>>> from music21 import * >>> o = corpus.parse('josquin/milleRegrets') >>> s = o.mergeScores() >>> s.metadata.title 'Mille regrets' >>> len(s.parts) 4
- show(fmt=None, app=None)¶
Displays an object in a format provided by the fmt argument or, if not provided, the format set in the user’s Environment.
This method overrides the behavior specified in Music21Object for all formats besides explicit lily.x calls.
- write(fmt=None, fp=None)¶
Displays an object in a format provided by the fmt argument or, if not provided, the format set in the user’s Environment.
This method overrides the behavior specified in Music21Object for all formats besides explicit lily.x calls.
Methods inherited from Stream: append(), insert(), insertAndShift(), transpose(), augmentOrDiminish(), scaleOffsets(), scaleDurations(), activateVariants(), addGroupForElements(), allPlayingWhileSounding(), analyze(), attachIntervalsBetweenStreams(), attachMelodicIntervals(), attributeCount(), bestClef(), chordify(), expandRepeats(), explode(), extendDuration(), extendDurationAndGetBoundaries(), extendTies(), extractContext(), findConsecutiveNotes(), findGaps(), flattenUnnecessaryVoices(), getClefs(), getElementAfterElement(), getElementAfterOffset(), getElementAtOrAfter(), getElementAtOrBefore(), getElementBeforeElement(), getElementBeforeOffset(), getElementById(), getElementByObjectId(), getElementsByClass(), getElementsByGroup(), getElementsByOffset(), getElementsNotOfClass(), getInstrument(), getInstruments(), getKeySignatures(), getOffsetByElement(), getOverlaps(), getSimultaneous(), getTimeSignatures(), groupCount(), groupElementsByOffset(), hasElement(), hasElementByObjectId(), hasElementOfClass(), hasMeasures(), hasPartLikeStreams(), hasVoices(), haveAccidentalsBeenMade(), haveBeamsBeenMade(), index(), insertAtNativeOffset(), insertIntoNoteOrChord(), internalize(), invertDiatonic(), isSequence(), isTwelveTone(), isWellFormedNotation(), makeAccidentals(), makeBeams(), makeChords(), makeImmutable(), makeMeasures(), makeMutable(), makeNotation(), makeRests(), makeTies(), makeTupletBrackets(), makeVoices(), measure(), measureOffsetMap(), measureTemplate(), measures(), melodicIntervals(), mergeElements(), metronomeMarkBoundaries(), pitchAttributeCount(), playingWhenAttacked(), plot(), pop(), quantize(), realizeOrnaments(), recurse(), remove(), removeByClass(), removeByNotOfClass(), repeatAppend(), repeatInsert(), replace(), restoreActiveSites(), setDerivation(), setupSerializationScaffold(), shiftElements(), showVariantAsOssialikePart(), simultaneousAttacks(), sliceAtOffsets(), sliceByBeat(), sliceByGreatestDivisor(), sliceByQuarterLengths(), sort(), splitAtQuarterLength(), splitByClass(), storeAtEnd(), stripTies(), teardownSerializationScaffold(), toSoundingPitch(), toWrittenPitch(), transferOffsetToElements(), trimPlayingWhileSounding(), unwrapWeakref(), voicesToParts(), wrapWeakref()
Methods inherited from Music21Object: addContext(), addLocation(), addLocationAndActiveSite(), freezeIds(), getAllContextsByClass(), getCommonSiteIds(), getCommonSites(), getContextAttr(), getContextByClass(), getOffsetBySite(), getSiteIds(), getSites(), getSpannerSites(), hasContext(), hasSite(), hasSpannerSite(), hasVariantSite(), isClassOrSubclass(), mergeAttributes(), next(), previous(), purgeLocations(), purgeOrphans(), purgeUndeclaredIds(), removeLocationBySite(), removeLocationBySiteId(), searchActiveSiteByAttr(), setContextAttr(), setOffsetBySite(), splitAtDurations(), splitByQuarterLengths(), unfreezeIds()
Methods inherited from JSONSerializer: jsonAttributes(), jsonComponentFactory(), jsonPrint(), jsonRead(), jsonWrite()
Inherits from: Stream, Music21Object, JSONSerializer
A Stream subclass for designating music that is considered a single part.
When put into a Score object, Part objects are all collected in the Score.parts call. Otherwise they mostly work like generic Streams.
Generally the hierarchy goes: Score > Part > Measure > Voice, but you are not required to stick to this.
Part groupings (piano braces, etc.) are found in the music21.layout module in the StaffGroup Spanner object.
Inherits from: Part, Stream, Music21Object, JSONSerializer
A Part subclass for designating music that is represented on a single staff but may only be one of many staffs for a single part.
Inherits from: Stream, Music21Object, JSONSerializer
A Stream subclass for handling multi-part music.
Absolutely optional (the largest containing Stream in a piece could be a generic Stream, or a Part, or a Staff). And Scores can be embedded in other Scores (in fact, our original thought was to call this class a Fragment because of this possibility of continuous embedding), but we figure that many people will like calling the largest container a Score and that this will become a standard.
Score attributes
Attributes inherited from Stream: isMeasure, isStream, isFlat, autoSort, isSorted, flattenedRepresentationOf
Attributes inherited from Music21Object: classSortOrder, isSpanner, isVariant, id, groups, hideObjectOnPrint
Score properties
- parts¶
Return all Part objects in a Score.
>>> from music21 import * >>> s = corpus.parse('bach/bwv66.6') >>> parts = s.parts >>> len(parts) 4Properties inherited from Stream: notes, pitches, atSoundingPitch, beat, beatDuration, beatStr, beatStrength, derivationChain, derivationMethod, derivesFrom, duration, elements, finalBarline, flat, highestOffset, highestTime, isGapless, lowestOffset, metadata, midiFile, musicxml, mx, notesAndRests, offsetMap, rootDerivation, seconds, secondsMap, semiFlat, sorted, spannerBundle, spanners, variants, voices
Properties inherited from Music21Object: activeSite, classes, derivationHierarchy, isGrace, measureNumber, offset, priority
Properties inherited from JSONSerializer: json
Score methods
- expandRepeats()¶
Expand all repeats, as well as all repeat indications given by text expressions such as D.C. al Segno.
This method always returns a new Stream, with deepcopies of all contained elements at all level.
- flattenParts(classFilterList=['Note', 'Chord'])¶
Given a Score, combine all Parts into a single Part with all elements found in each Measure of the Score.
The classFilterList can be used to specify which objects contained in Measures are transferred.
>>> from music21 import * >>> s = corpus.parse('bwv66.6') >>> len(s.parts) 4 >>> len(s.flat.notes) 165 >>> post = s.flattenParts() >>> 'Part' in post.classes True >>> len(post.flat.notes) 165
- implode()¶
Reduce a polyphonic work into one or more staves.
- makeNotation(meterStream=None, refStreamOrTimeRange=None, inPlace=False, bestClef=False, **subroutineKeywords)¶
This method overrides the makeNotation method on Stream, such that a Score object with one or more Parts or Streams that may not contain well-formed notation may be transformed and replaced by well-formed notation.
If inPlace is True, this is done in-place; if inPlace is False, this returns a modified deep copy.
- measure(measureNumber, collect=[<class 'music21.clef.Clef'>, <class 'music21.meter.TimeSignature'>, <class 'music21.instrument.Instrument'>, <class 'music21.key.KeySignature'>], gatherSpanners=True)¶
Given a measure number, return a single Measure object if the Measure number exists, otherwise return None.
This method overrides the measures() method on Stream. This creates a new Score stream that has the same measure range for all Parts.
>>> from music21 import corpus >>> a = corpus.parse('bach/bwv324.xml') >>> # contains 1 measure >>> len(a.measure(3).parts[0].getElementsByClass('Measure')) 1
- measureOffsetMap(classFilterList=None)¶
This method overrides the measureOffsetMap() method of Stream. This creates a map based on all contained Parts in this Score. Measures found in multiple Parts with the same offset will be appended to the same list.
If no parts are found in the score, then the normal measureOffsetMap() routine is called.
This method is smart and does not assume that all Parts have measures with identical offsets.
- measures(numberStart, numberEnd, collect=['Clef', 'TimeSignature', 'Instrument', 'KeySignature'], gatherSpanners=True, searchContext=False)¶
This method override the measures() method on Stream. This creates a new Score stream that has the same measure range for all Parts.
The collect argument is a list of classes that will be collected.
>>> from music21 import * >>> s = corpus.parse('bwv66.6') >>> post = s.measures(3,5) # range is inclusive, i.e., [3, 5] >>> len(post.parts) 4 >>> len(post.parts[0].getElementsByClass('Measure')) 3 >>> len(post.parts[1].getElementsByClass('Measure')) 3
- partsToVoices(voiceAllocation=2, permitOneVoicePerPart=False)¶
Given a multi-part Score, return a new Score that combines parts into voices.
The voiceAllocation parameter sets the maximum number of voices per Part.
The permitOneVoicePerPart parameter, if True, will encode a single voice inside a single Part, rather than leaving it as a single Part alone, with no voices.
>>> from music21 import * >>> s = corpus.parse('bwv66.6') >>> len(s.flat.notes) 165 >>> post = s.partsToVoices(voiceAllocation=4) >>> len(post.parts) 1 >>> len(post.parts[0].getElementsByClass('Measure')[0].voices) 4 >>> len(post.flat.notes) 165
- sliceByGreatestDivisor(inPlace=True, addTies=True)¶
Slice all duration of all part by the minimum duration that can be summed to each concurrent duration.
Overrides method defined on Stream.
Methods inherited from Stream: append(), insert(), insertAndShift(), transpose(), augmentOrDiminish(), scaleOffsets(), scaleDurations(), activateVariants(), addGroupForElements(), allPlayingWhileSounding(), analyze(), attachIntervalsBetweenStreams(), attachMelodicIntervals(), attributeCount(), bestClef(), chordify(), explode(), extendDuration(), extendDurationAndGetBoundaries(), extendTies(), extractContext(), findConsecutiveNotes(), findGaps(), flattenUnnecessaryVoices(), getClefs(), getElementAfterElement(), getElementAfterOffset(), getElementAtOrAfter(), getElementAtOrBefore(), getElementBeforeElement(), getElementBeforeOffset(), getElementById(), getElementByObjectId(), getElementsByClass(), getElementsByGroup(), getElementsByOffset(), getElementsNotOfClass(), getInstrument(), getInstruments(), getKeySignatures(), getOffsetByElement(), getOverlaps(), getSimultaneous(), getTimeSignatures(), groupCount(), groupElementsByOffset(), hasElement(), hasElementByObjectId(), hasElementOfClass(), hasMeasures(), hasPartLikeStreams(), hasVoices(), haveAccidentalsBeenMade(), haveBeamsBeenMade(), index(), insertAtNativeOffset(), insertIntoNoteOrChord(), internalize(), invertDiatonic(), isSequence(), isTwelveTone(), isWellFormedNotation(), makeAccidentals(), makeBeams(), makeChords(), makeImmutable(), makeMeasures(), makeMutable(), makeRests(), makeTies(), makeTupletBrackets(), makeVoices(), measureTemplate(), melodicIntervals(), mergeElements(), metronomeMarkBoundaries(), pitchAttributeCount(), playingWhenAttacked(), plot(), pop(), quantize(), realizeOrnaments(), recurse(), remove(), removeByClass(), removeByNotOfClass(), repeatAppend(), repeatInsert(), replace(), restoreActiveSites(), setDerivation(), setupSerializationScaffold(), shiftElements(), showVariantAsOssialikePart(), simultaneousAttacks(), sliceAtOffsets(), sliceByBeat(), sliceByQuarterLengths(), sort(), splitAtQuarterLength(), splitByClass(), storeAtEnd(), stripTies(), teardownSerializationScaffold(), toSoundingPitch(), toWrittenPitch(), transferOffsetToElements(), trimPlayingWhileSounding(), unwrapWeakref(), voicesToParts(), wrapWeakref()
Methods inherited from Music21Object: addContext(), addLocation(), addLocationAndActiveSite(), freezeIds(), getAllContextsByClass(), getCommonSiteIds(), getCommonSites(), getContextAttr(), getContextByClass(), getOffsetBySite(), getSiteIds(), getSites(), getSpannerSites(), hasContext(), hasSite(), hasSpannerSite(), hasVariantSite(), isClassOrSubclass(), mergeAttributes(), next(), previous(), purgeLocations(), purgeOrphans(), purgeUndeclaredIds(), removeLocationBySite(), removeLocationBySiteId(), searchActiveSiteByAttr(), setContextAttr(), setOffsetBySite(), show(), splitAtDurations(), splitByQuarterLengths(), unfreezeIds(), write()
Methods inherited from JSONSerializer: jsonAttributes(), jsonComponentFactory(), jsonPrint(), jsonRead(), jsonWrite()
Inherits from: Stream, Music21Object, JSONSerializer
For advanced use. This Stream subclass is only used inside of a Spanner object to provide object storage of connected elements (things the Spanner spans).
This subclass name can be used to search in an object’s DefinedContexts and find any and all locations that are SpannerStorage objects.
A spannerParent keyword argument must be provided by the Spanner in creation.
SpannerStorage attributes
Attributes without Documentation: spannerParent
Attributes inherited from Stream: isMeasure, isStream, isFlat, autoSort, isSorted, flattenedRepresentationOf
Attributes inherited from Music21Object: classSortOrder, isSpanner, isVariant, id, groups, hideObjectOnPrint
SpannerStorage properties
Properties inherited from Stream: notes, pitches, atSoundingPitch, beat, beatDuration, beatStr, beatStrength, derivationChain, derivationMethod, derivesFrom, duration, elements, finalBarline, flat, highestOffset, highestTime, isGapless, lowestOffset, metadata, midiFile, musicxml, mx, notesAndRests, offsetMap, rootDerivation, seconds, secondsMap, semiFlat, sorted, spannerBundle, spanners, variants, voices
Properties inherited from Music21Object: activeSite, classes, derivationHierarchy, isGrace, measureNumber, offset, priority
Properties inherited from JSONSerializer: json
SpannerStorage methods
Methods inherited from Stream: append(), insert(), insertAndShift(), transpose(), augmentOrDiminish(), scaleOffsets(), scaleDurations(), activateVariants(), addGroupForElements(), allPlayingWhileSounding(), analyze(), attachIntervalsBetweenStreams(), attachMelodicIntervals(), attributeCount(), bestClef(), chordify(), expandRepeats(), explode(), extendDuration(), extendDurationAndGetBoundaries(), extendTies(), extractContext(), findConsecutiveNotes(), findGaps(), flattenUnnecessaryVoices(), getClefs(), getElementAfterElement(), getElementAfterOffset(), getElementAtOrAfter(), getElementAtOrBefore(), getElementBeforeElement(), getElementBeforeOffset(), getElementById(), getElementByObjectId(), getElementsByClass(), getElementsByGroup(), getElementsByOffset(), getElementsNotOfClass(), getInstrument(), getInstruments(), getKeySignatures(), getOffsetByElement(), getOverlaps(), getSimultaneous(), getTimeSignatures(), groupCount(), groupElementsByOffset(), hasElement(), hasElementByObjectId(), hasElementOfClass(), hasMeasures(), hasPartLikeStreams(), hasVoices(), haveAccidentalsBeenMade(), haveBeamsBeenMade(), index(), insertAtNativeOffset(), insertIntoNoteOrChord(), internalize(), invertDiatonic(), isSequence(), isTwelveTone(), isWellFormedNotation(), makeAccidentals(), makeBeams(), makeChords(), makeImmutable(), makeMeasures(), makeMutable(), makeNotation(), makeRests(), makeTies(), makeTupletBrackets(), makeVoices(), measure(), measureOffsetMap(), measureTemplate(), measures(), melodicIntervals(), mergeElements(), metronomeMarkBoundaries(), pitchAttributeCount(), playingWhenAttacked(), plot(), pop(), quantize(), realizeOrnaments(), recurse(), remove(), removeByClass(), removeByNotOfClass(), repeatAppend(), repeatInsert(), replace(), restoreActiveSites(), setDerivation(), setupSerializationScaffold(), shiftElements(), showVariantAsOssialikePart(), simultaneousAttacks(), sliceAtOffsets(), sliceByBeat(), sliceByGreatestDivisor(), sliceByQuarterLengths(), sort(), splitAtQuarterLength(), splitByClass(), storeAtEnd(), stripTies(), teardownSerializationScaffold(), toSoundingPitch(), toWrittenPitch(), transferOffsetToElements(), trimPlayingWhileSounding(), unwrapWeakref(), voicesToParts(), wrapWeakref()
Methods inherited from Music21Object: addContext(), addLocation(), addLocationAndActiveSite(), freezeIds(), getAllContextsByClass(), getCommonSiteIds(), getCommonSites(), getContextAttr(), getContextByClass(), getOffsetBySite(), getSiteIds(), getSites(), getSpannerSites(), hasContext(), hasSite(), hasSpannerSite(), hasVariantSite(), isClassOrSubclass(), mergeAttributes(), next(), previous(), purgeLocations(), purgeOrphans(), purgeUndeclaredIds(), removeLocationBySite(), removeLocationBySiteId(), searchActiveSiteByAttr(), setContextAttr(), setOffsetBySite(), show(), splitAtDurations(), splitByQuarterLengths(), unfreezeIds(), write()
Methods inherited from JSONSerializer: jsonAttributes(), jsonComponentFactory(), jsonPrint(), jsonRead(), jsonWrite()
An Iterator object used to handle iteration of Streams. The __iter__() method returns this object, passing a reference to self.
Note that this iterator automatically sets the active site of returned elements to the the source Stream.
StreamIterator methods
- next()¶
No documentation.
Inherits from: Stream, Music21Object, JSONSerializer
For advanced use. This Stream subclass is only used inside of a Variant object to provide object storage of connected elements (things the Variant defines).
This subclass name can be used to search in an object’s DefinedContexts and find any and all locations that are VariantStorage objects.
A variantParent keyword argument must be provided by the Variant in creation.
VariantStorage attributes
Attributes without Documentation: variantParent
Attributes inherited from Stream: isMeasure, isStream, isFlat, autoSort, isSorted, flattenedRepresentationOf
Attributes inherited from Music21Object: classSortOrder, isSpanner, isVariant, id, groups, hideObjectOnPrint
VariantStorage properties
Properties inherited from Stream: notes, pitches, atSoundingPitch, beat, beatDuration, beatStr, beatStrength, derivationChain, derivationMethod, derivesFrom, duration, elements, finalBarline, flat, highestOffset, highestTime, isGapless, lowestOffset, metadata, midiFile, musicxml, mx, notesAndRests, offsetMap, rootDerivation, seconds, secondsMap, semiFlat, sorted, spannerBundle, spanners, variants, voices
Properties inherited from Music21Object: activeSite, classes, derivationHierarchy, isGrace, measureNumber, offset, priority
Properties inherited from JSONSerializer: json
VariantStorage methods
Methods inherited from Stream: append(), insert(), insertAndShift(), transpose(), augmentOrDiminish(), scaleOffsets(), scaleDurations(), activateVariants(), addGroupForElements(), allPlayingWhileSounding(), analyze(), attachIntervalsBetweenStreams(), attachMelodicIntervals(), attributeCount(), bestClef(), chordify(), expandRepeats(), explode(), extendDuration(), extendDurationAndGetBoundaries(), extendTies(), extractContext(), findConsecutiveNotes(), findGaps(), flattenUnnecessaryVoices(), getClefs(), getElementAfterElement(), getElementAfterOffset(), getElementAtOrAfter(), getElementAtOrBefore(), getElementBeforeElement(), getElementBeforeOffset(), getElementById(), getElementByObjectId(), getElementsByClass(), getElementsByGroup(), getElementsByOffset(), getElementsNotOfClass(), getInstrument(), getInstruments(), getKeySignatures(), getOffsetByElement(), getOverlaps(), getSimultaneous(), getTimeSignatures(), groupCount(), groupElementsByOffset(), hasElement(), hasElementByObjectId(), hasElementOfClass(), hasMeasures(), hasPartLikeStreams(), hasVoices(), haveAccidentalsBeenMade(), haveBeamsBeenMade(), index(), insertAtNativeOffset(), insertIntoNoteOrChord(), internalize(), invertDiatonic(), isSequence(), isTwelveTone(), isWellFormedNotation(), makeAccidentals(), makeBeams(), makeChords(), makeImmutable(), makeMeasures(), makeMutable(), makeNotation(), makeRests(), makeTies(), makeTupletBrackets(), makeVoices(), measure(), measureOffsetMap(), measureTemplate(), measures(), melodicIntervals(), mergeElements(), metronomeMarkBoundaries(), pitchAttributeCount(), playingWhenAttacked(), plot(), pop(), quantize(), realizeOrnaments(), recurse(), remove(), removeByClass(), removeByNotOfClass(), repeatAppend(), repeatInsert(), replace(), restoreActiveSites(), setDerivation(), setupSerializationScaffold(), shiftElements(), showVariantAsOssialikePart(), simultaneousAttacks(), sliceAtOffsets(), sliceByBeat(), sliceByGreatestDivisor(), sliceByQuarterLengths(), sort(), splitAtQuarterLength(), splitByClass(), storeAtEnd(), stripTies(), teardownSerializationScaffold(), toSoundingPitch(), toWrittenPitch(), transferOffsetToElements(), trimPlayingWhileSounding(), unwrapWeakref(), voicesToParts(), wrapWeakref()
Methods inherited from Music21Object: addContext(), addLocation(), addLocationAndActiveSite(), freezeIds(), getAllContextsByClass(), getCommonSiteIds(), getCommonSites(), getContextAttr(), getContextByClass(), getOffsetBySite(), getSiteIds(), getSites(), getSpannerSites(), hasContext(), hasSite(), hasSpannerSite(), hasVariantSite(), isClassOrSubclass(), mergeAttributes(), next(), previous(), purgeLocations(), purgeOrphans(), purgeUndeclaredIds(), removeLocationBySite(), removeLocationBySiteId(), searchActiveSiteByAttr(), setContextAttr(), setOffsetBySite(), show(), splitAtDurations(), splitByQuarterLengths(), unfreezeIds(), write()
Methods inherited from JSONSerializer: jsonAttributes(), jsonComponentFactory(), jsonPrint(), jsonRead(), jsonWrite()
Inherits from: Stream, Music21Object, JSONSerializer
A Stream subclass for declaring that all the music in the stream belongs to a certain “voice” for analysis or display purposes.
Note that both Finale’s Layers and Voices as concepts are considered Voices here.