Coverage for pygeodesy/iters.py: 97%
203 statements
« prev ^ index » next coverage.py v7.2.2, created at 2024-05-15 16:36 -0400
« prev ^ index » next coverage.py v7.2.2, created at 2024-05-15 16:36 -0400
2# -*- coding: utf-8 -*-
4u'''Iterators with options.
6Iterator classes L{LatLon2PsxyIter} and L{PointsIter} to iterate
7over iterables, lists, sets, tuples, etc. with optional loop-back to
8the initial items, skipping of duplicate items and copying of the
9iterated items.
10'''
12from pygeodesy.basics import islistuple, issubclassof, len2, \
13 map2, _passarg
14# from pygeodesy.constants import _1_0 # from .utily
15from pygeodesy.errors import _IndexError, LenError, PointsError, \
16 _TypeError, _ValueError
17# from pygeodesy.internals import _passarg # from .basics
18from pygeodesy.interns import NN, _0_, _composite_, _few_, \
19 _latlon_, _points_, _too_
20from pygeodesy.lazily import _ALL_DOCS, _ALL_LAZY, _ALL_MODS as _MODS
21from pygeodesy.named import Fmt, _Named, property_RO
22from pygeodesy.namedTuples import Point3Tuple, Points2Tuple
23# from pygeodesy.props import property_RO # from .named
24# from pygeodesy.streprs import Fmt # from .named
25from pygeodesy.units import Int, Radius
26from pygeodesy.utily import degrees2m, _Wrap, _1_0
28__all__ = _ALL_LAZY.iters
29__version__ = '23.12.14'
31_items_ = 'items'
32_iterNumpy2len = 1 # adjustable for testing purposes
33_NOTHING = object() # unique
36class _BaseIter(_Named):
37 '''(INTERNAL) Iterator over items with loop-back and de-duplication.
39 @see: Luciano Ramalho, "Fluent Python", O'Reilly, 2016 p. 418+, 2022 p. 600+
40 '''
41 _closed = True
42 _copies = ()
43 _dedup = False
44 _Error = LenError
45 _items = None
46 _len = 0
47 _loop = ()
48 _looped = False
49 _name = _items_
50 _prev = _NOTHING
51 _wrap = False
53 def __init__(self, items, loop=0, dedup=False, Error=None, name=NN):
54 '''New iterator over an iterable of B{C{items}}.
56 @arg items: Iterable (any C{type}, except composites).
57 @kwarg loop: Number of loop-back items, also initial enumerate and
58 iterate index (non-negative C{int}).
59 @kwarg dedup: Skip duplicate items (C{bool}).
60 @kwarg Error: Error to raise (L{LenError}).
61 @kwarg name: Optional name (C{str}).
63 @raise Error: Invalid B{C{items}} or sufficient number of B{C{items}}.
65 @raise TypeError: Composite B{C{items}}.
66 '''
67 if dedup:
68 self._dedup = True
69 if issubclassof(Error, Exception):
70 self._Error = Error
71 if name:
72 self.rename(name)
74 if islistuple(items): # range in Python 2
75 self._items = items
76 elif _MODS.booleans.isBoolean(items):
77 raise _TypeError(points=_composite_)
78# XXX if hasattr(items, 'next') or hasattr(items, '__length_hint__'):
79# XXX # handle reversed, iter, etc. items types
80 self._iter = iter(items)
81 self._indx = -1
82 if Int(loop) > 0:
83 try:
84 self._loop = tuple(self.next for _ in range(loop))
85 if self.loop != loop:
86 raise RuntimeError # force Error
87 except (RuntimeError, StopIteration):
88 raise self._Error(self.name, self.loop, txt=_too_(_few_))
90 @property_RO
91 def copies(self):
92 '''Get the saved copies, if any (C{tuple} or C{list}) and only I{once}.
93 '''
94 cs = self._copies
95 if cs:
96 self._copies = ()
97 return cs
99 @property_RO
100 def dedup(self):
101 '''Get the de-duplication setting (C{bool}).
102 '''
103 return self._dedup
105 def enumerate(self, closed=False, copies=False, dedup=False):
106 '''Yield all items, each as a 2-tuple C{(index, item)}.
108 @kwarg closed: Loop back to the first B{C{point(s)}}.
109 @kwarg copies: Make a copy of all B{C{items}} (C{bool}).
110 @kwarg dedup: Set de-duplication in loop-back (C{bool}).
111 '''
112 for item in self.iterate(closed=closed, copies=copies, dedup=dedup):
113 yield self._indx, item
115 def __getitem__(self, index):
116 '''Get the item(s) at the given B{C{index}} or C{slice}.
118 @raise IndexError: Invalid B{C{index}}, beyond B{C{loop}}.
119 '''
120 t = self._items or self._copies or self._loop
121 try: # Luciano Ramalho, "Fluent Python", O'Reilly, 2016 p. 293+, 2022 p. 408+
122 if isinstance(index, slice):
123 return t[index.start:index.stop:index.step]
124 else:
125 return t[index]
126 except IndexError as x:
127 t = Fmt.SQUARE(self.name, index)
128 raise _IndexError(str(x), txt=t, cause=x)
130 def __iter__(self): # PYCHOK no cover
131 '''Make this iterator C{iterable}.
132 '''
133 # Luciano Ramalho, "Fluent Python", O'Reilly, 2016 p. 421, 2022 p. 604+
134 return self.iterate() # XXX or self?
136 def iterate(self, closed=False, copies=False, dedup=False):
137 '''Yield all items, each as C{item}.
139 @kwarg closed: Loop back to the first B{C{point(s)}}.
140 @kwarg copies: Make a copy of all B{C{items}} (C{bool}).
141 @kwarg dedup: Set de-duplication in loop-back (C{bool}).
143 @raise Error: Using C{B{closed}=True} without B{C{loop}}-back.
144 '''
145 if closed and not self.loop:
146 raise self._Error(closed=closed, loop=self.loop)
148 if copies:
149 if self._items:
150 self._copies = self._items
151 self._items = _copy = None
152 else:
153 self._copies = list(self._loop)
154 _copy = self._copies.append
155 else: # del B{C{items}} reference
156 self._items = _copy = None
158 self._closed = closed
159 self._looped = False
160 if self._iter:
161 try:
162 _next_ = self.next_
163 if _copy:
164 while True:
165 item = _next_(dedup=dedup)
166 _copy(item)
167 yield item
168 else:
169 while True:
170 yield _next_(dedup=dedup)
171 except StopIteration:
172 self._iter = () # del self._iter, prevent re-iterate
174 def __len__(self):
175 '''Get the number of items seen so far.
176 '''
177 return self._len
179 @property_RO
180 def loop(self):
181 '''Get the B{C{loop}} setting (C{int}), C{0} for non-loop-back.
182 '''
183 return len(self._loop)
185 @property_RO
186 def looped(self):
187 '''In this C{Iter}ator in loop-back? (C{bool}).
188 '''
189 return self._looped
191 @property_RO
192 def next(self):
193 '''Get the next item.
194 '''
195 return self._next_dedup() if self._dedup else self._next(False)
197# __next__ # NO __next__ AND __iter__ ... see Luciano Ramalho,
198# # "Fluent Python", O'Reilly, 2016 p. 426, 2022 p. 610
200 def next_(self, dedup=False):
201 '''Return the next item.
203 @kwarg dedup: Set de-duplication for loop-back (C{bool}).
204 '''
205 return self._next_dedup() if self._dedup else self._next(dedup)
207 def _next(self, dedup):
208 '''Return the next item, regardless.
210 @arg dedup: Set de-duplication for loop-back (C{bool}).
211 '''
212 try:
213 self._indx += 1
214 self._len = self._indx # max(_len, _indx)
215 self._prev = item = next(self._iter)
216 return item
217 except StopIteration:
218 pass
219 if self._closed and self._loop: # loop back
220 self._dedup = bool(dedup or self._dedup)
221 self._indx = 0
222 self._iter = iter(self._loop)
223 self._loop = ()
224 self._looped = True
225 return next(self._iter)
227 def _next_dedup(self):
228 '''Return the next item, different from the previous one.
229 '''
230 prev = self._prev
231 item = self._next(True)
232 if prev is not _NOTHING:
233 while item == prev:
234 item = self._next(True)
235 return item
238class PointsIter(_BaseIter):
239 '''Iterator for C{points} with optional loop-back and copies.
240 '''
241 _base = None
242 _Error = PointsError
244 def __init__(self, points, loop=0, base=None, dedup=False, wrap=False, name=NN):
245 '''New L{PointsIter} iterator.
247 @arg points: C{Iterable} or C{list}, C{sequence}, C{set}, C{tuple},
248 etc. (C{point}s).
249 @kwarg loop: Number of loop-back points, also initial C{enumerate} and
250 C{iterate} index (non-negative C{int}).
251 @kwarg base: Optional B{C{points}} instance for type checking (C{any}).
252 @kwarg dedup: Skip duplicate points (C{bool}).
253 @kwarg wrap: If C{True}, wrap or I{normalize} the enum-/iterated
254 B{C{points}} (C{bool}).
255 @kwarg name: Optional name (C{str}).
257 @raise PointsError: Insufficient number of B{C{points}}.
259 @raise TypeError: Some B{C{points}} are not B{C{base}}.
260 '''
261 _BaseIter.__init__(self, points, loop=loop, dedup=dedup, name=name or _points_)
263 if base and not (isNumpy2(points) or isTuple2(points)):
264 self._base = base
265 if wrap:
266 self._wrap = True
268 def enumerate(self, closed=False, copies=False): # PYCHOK signature
269 '''Iterate and yield each point as a 2-tuple C{(index, point)}.
271 @kwarg closed: Loop back to the first B{C{point(s)}}, de-dup'ed (C{bool}).
272 @kwarg copies: Save a copy of all B{C{points}} (C{bool}).
274 @raise PointsError: Insufficient number of B{C{points}} or using
275 C{B{closed}=True} without B{C{loop}}-back.
277 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.
278 '''
279 for p in self.iterate(closed=closed, copies=copies):
280 yield self._indx, p
282 def iterate(self, closed=False, copies=False): # PYCHOK signature
283 '''Iterate through all B{C{points}} starting at index C{loop}.
285 @kwarg closed: Loop back to the first B{C{point(s)}}, de-dup'ed (C{bool}).
286 @kwarg copies: Save a copy of all B{C{points}} (C{bool}).
288 @raise PointsError: Insufficient number of B{C{points}} or using
289 C{B{closed}=True} without B{C{loop}}-back.
291 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.
292 '''
293 if self._base:
294 _oth = self._base.others
295 _fmt = Fmt.SQUARE(points=0).replace
296 else:
297 _oth = _fmt = None
299 n = self.loop if self._iter else 0
300 _p = _Wrap.point if self._wrap else _passarg # and _Wrap.normal is not None
301 for p in _BaseIter.iterate(self, closed=closed, copies=copies, dedup=closed):
302 if _oth:
303 _oth(p, name=_fmt(_0_, str(self._indx)), up=2)
304 yield _p(p)
305 n += 1
306 if n < (4 if closed else 2):
307 raise self._Error(self.name, n, txt=_too_(_few_))
310class LatLon2PsxyIter(PointsIter):
311 '''Iterate and convert for C{points} with optional loop-back and copies.
312 '''
313 _deg2m = None
314 _radius = None # keep degrees
315 _wrap = True
317 def __init__(self, points, loop=0, base=None, wrap=True, radius=None,
318 dedup=False, name=_latlon_):
319 '''New L{LatLon2PsxyIter} iterator.
321 @note: The C{LatLon} latitude is considered the I{pseudo-y} and
322 longitude the I{pseudo-x} coordinate, like L{LatLon2psxy}.
324 @arg points: C{Iterable} or C{list}, C{sequence}, C{set}, C{tuple},
325 etc. (C{LatLon}[]).
326 @kwarg loop: Number of loop-back points, also initial C{enumerate} and
327 C{iterate} index (non-negative C{int}).
328 @kwarg base: Optional B{C{points}} instance for type checking (C{any}).
329 @kwarg wrap: If C{True}, wrap or I{normalize} the enum-/iterated
330 B{C{points}} (C{bool}).
331 @kwarg radius: Mean earth radius (C{meter}) for conversion from
332 C{degrees} to C{meter} (or C{radians} if C{B{radius}=1}).
333 @kwarg dedup: Skip duplicate points (C{bool}).
334 @kwarg name: Optional name (C{str}).
336 @raise PointsError: Insufficient number of B{C{points}}.
338 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.
339 '''
340 PointsIter.__init__(self, points, loop=loop, base=base, dedup=dedup, name=name)
341 if not wrap:
342 self._wrap = False
343 if radius:
344 self._radius = r = Radius(radius)
345 self._deg2m = degrees2m(_1_0, r)
347 def __getitem__(self, index):
348 '''Get the point(s) at the given B{C{index}} or C{slice}.
350 @raise IndexError: Invalid B{C{index}}, beyond B{C{loop}}.
351 '''
352 ll = PointsIter.__getitem__(self, index)
353 if isinstance(index, slice):
354 return map2(self._point3Tuple, ll)
355 else:
356 return self._point3Tuple(ll)
358 def enumerate(self, closed=False, copies=False): # PYCHOK signature
359 '''Iterate and yield each point as a 2-tuple C{(index, L{Point3Tuple})}.
361 @kwarg closed: Loop back to the first B{C{point(s)}}, de-dup'ed (C{bool}).
362 @kwarg copies: Save a copy of all B{C{points}} (C{bool}).
364 @raise PointsError: Insufficient number of B{C{points}} or using
365 C{B{closed}=True} without B{C{loop}}-back.
367 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.
368 '''
369 return PointsIter.enumerate(self, closed=closed, copies=copies)
371 def iterate(self, closed=False, copies=False): # PYCHOK signature
372 '''Iterate the B{C{points}} starting at index B{C{loop}} and
373 yield each as a L{Point3Tuple}C{(x, y, ll)}.
375 @kwarg closed: Loop back to the first B{C{point(s)}}, de-dup'ed (C{bool}).
376 @kwarg copies: Save a copy of all B{C{points}} (C{bool}).
378 @raise PointsError: Insufficient number of B{C{points}} or using
379 C{B{closed}=True} without B{C{loop}}-back.
381 @raise TypeError: Some B{C{points}} are not B{C{base}}-compatible.
382 '''
383 if self._deg2m not in (None, _1_0):
384 _p3 = self._point3Tuple
385 else:
386 def _p3(ll): # PYCHOK redef
387 return Point3Tuple(ll.lon, ll.lat, ll)
389 for ll in PointsIter.iterate(self, closed=closed, copies=copies):
390 yield _p3(ll)
392 def _point3Tuple(self, ll):
393 '''(INTERNAL) Create a L{Point3Tuple} for point B{C{ll}}.
394 '''
395 x, y = ll.lon, ll.lat # note, x, y = lon, lat
396 d = self._deg2m
397 if d: # convert degrees
398 x *= d
399 y *= d
400 return Point3Tuple(x, y, ll)
403def _imdex2(closed, n): # PYCHOK by .clipy
404 '''(INTERNAL) Return first and second index of C{range(B{n})}.
405 '''
406 return (n-1, 0) if closed else (0, 1)
409def isNumpy2(obj):
410 '''Check for a B{C{Numpy2LatLon}} points wrapper.
412 @arg obj: The object (any C{type}).
414 @return: C{True} if B{C{obj}} is a B{C{Numpy2LatLon}}
415 instance, C{False} otherwise.
416 '''
417 # isinstance(self, (Numpy2LatLon, ...))
418 return getattr(obj, isNumpy2.__name__, False)
421def isPoints2(obj):
422 '''Check for a B{C{LatLon2psxy}} points wrapper.
424 @arg obj: The object (any C{type}).
426 @return: C{True} if B{C{obj}} is a B{C{LatLon2psxy}}
427 instance, C{False} otherwise.
428 '''
429 # isinstance(self, (LatLon2psxy, ...))
430 return getattr(obj, isPoints2.__name__, False)
433def isTuple2(obj):
434 '''Check for a B{C{Tuple2LatLon}} points wrapper.
436 @arg obj: The object (any).
438 @return: C{True} if B{C{obj}} is a B{C{Tuple2LatLon}}
439 instance, C{False} otherwise.
440 '''
441 # isinstance(self, (Tuple2LatLon, ...))
442 return getattr(obj, isTuple2.__name__, False)
445def iterNumpy2(obj):
446 '''Iterate over Numpy2 wrappers or other sequences exceeding
447 the threshold.
449 @arg obj: Points array, list, sequence, set, etc. (any).
451 @return: C{True} do, C{False} don't iterate.
452 '''
453 try:
454 return isNumpy2(obj) or len(obj) > _iterNumpy2len
455 except TypeError:
456 return False
459def iterNumpy2over(n=None):
460 '''Get or set the L{iterNumpy2} threshold.
462 @kwarg n: Optional, new threshold (C{int}).
464 @return: Previous threshold (C{int}).
466 @raise ValueError: Invalid B{C{n}}.
467 '''
468 global _iterNumpy2len
469 p = _iterNumpy2len
470 if n is not None:
471 try:
472 i = int(n)
473 if i > 0:
474 _iterNumpy2len = i
475 else:
476 raise ValueError
477 except (TypeError, ValueError):
478 raise _ValueError(n=n)
479 return p
482def points2(points, closed=True, base=None, Error=PointsError):
483 '''Check a path or polygon represented by points.
485 @arg points: The path or polygon points (C{LatLon}[])
486 @kwarg closed: Optionally, consider the polygon closed,
487 ignoring any duplicate or closing final
488 B{C{points}} (C{bool}).
489 @kwarg base: Optionally, check all B{C{points}} against
490 this base class, if C{None} don't check.
491 @kwarg Error: Exception to raise (C{ValueError}).
493 @return: A L{Points2Tuple}C{(number, points)} with the number
494 of points and the points C{list} or C{tuple}.
496 @raise PointsError: Insufficient number of B{C{points}}.
498 @raise TypeError: Some B{C{points}} are not B{C{base}}
499 compatible or composite B{C{points}}.
500 '''
501 if _MODS.booleans.isBoolean(points):
502 raise Error(points=points, txt=_composite_)
504 n, points = len2(points)
506 if closed:
507 # remove duplicate or closing final points
508 while n > 1 and points[n-1] in (points[0], points[n-2]):
509 n -= 1
510 # XXX following line is unneeded if points
511 # are always indexed as ... i in range(n)
512 points = points[:n] # XXX numpy.array slice is a view!
514 if n < (3 if closed else 1):
515 raise Error(points=n, txt=_too_(_few_))
517 if base and not (isNumpy2(points) or isTuple2(points)):
518 for i in range(n):
519 base.others(points[i], name=Fmt.SQUARE(points=i))
521 return Points2Tuple(n, points)
524__all__ += _ALL_DOCS(_BaseIter)
526# **) MIT License
527#
528# Copyright (C) 2016-2024 -- mrJean1 at Gmail -- All Rights Reserved.
529#
530# Permission is hereby granted, free of charge, to any person obtaining a
531# copy of this software and associated documentation files (the "Software"),
532# to deal in the Software without restriction, including without limitation
533# the rights to use, copy, modify, merge, publish, distribute, sublicense,
534# and/or sell copies of the Software, and to permit persons to whom the
535# Software is furnished to do so, subject to the following conditions:
536#
537# The above copyright notice and this permission notice shall be included
538# in all copies or substantial portions of the Software.
539#
540# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
541# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
542# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
543# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
544# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
545# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
546# OTHER DEALINGS IN THE SOFTWARE.