Coverage for /home/martinb/.local/share/virtualenvs/camcops/lib/python3.6/site-packages/numpy/core/_exceptions.py : 42%

Hot-keys on this page
r m x p toggle line displays
j k next/prev highlighted chunk
0 (zero) top of page
1 (one) first highlighted chunk
1"""
2Various richly-typed exceptions, that also help us deal with string formatting
3in python where it's easier.
5By putting the formatting in `__str__`, we also avoid paying the cost for
6users who silence the exceptions.
7"""
8from numpy.core.overrides import set_module
10def _unpack_tuple(tup):
11 if len(tup) == 1:
12 return tup[0]
13 else:
14 return tup
17def _display_as_base(cls):
18 """
19 A decorator that makes an exception class look like its base.
21 We use this to hide subclasses that are implementation details - the user
22 should catch the base type, which is what the traceback will show them.
24 Classes decorated with this decorator are subject to removal without a
25 deprecation warning.
26 """
27 assert issubclass(cls, Exception)
28 cls.__name__ = cls.__base__.__name__
29 cls.__qualname__ = cls.__base__.__qualname__
30 set_module(cls.__base__.__module__)(cls)
31 return cls
34class UFuncTypeError(TypeError):
35 """ Base class for all ufunc exceptions """
36 def __init__(self, ufunc):
37 self.ufunc = ufunc
40@_display_as_base
41class _UFuncBinaryResolutionError(UFuncTypeError):
42 """ Thrown when a binary resolution fails """
43 def __init__(self, ufunc, dtypes):
44 super().__init__(ufunc)
45 self.dtypes = tuple(dtypes)
46 assert len(self.dtypes) == 2
48 def __str__(self):
49 return (
50 "ufunc {!r} cannot use operands with types {!r} and {!r}"
51 ).format(
52 self.ufunc.__name__, *self.dtypes
53 )
56@_display_as_base
57class _UFuncNoLoopError(UFuncTypeError):
58 """ Thrown when a ufunc loop cannot be found """
59 def __init__(self, ufunc, dtypes):
60 super().__init__(ufunc)
61 self.dtypes = tuple(dtypes)
63 def __str__(self):
64 return (
65 "ufunc {!r} did not contain a loop with signature matching types "
66 "{!r} -> {!r}"
67 ).format(
68 self.ufunc.__name__,
69 _unpack_tuple(self.dtypes[:self.ufunc.nin]),
70 _unpack_tuple(self.dtypes[self.ufunc.nin:])
71 )
74@_display_as_base
75class _UFuncCastingError(UFuncTypeError):
76 def __init__(self, ufunc, casting, from_, to):
77 super().__init__(ufunc)
78 self.casting = casting
79 self.from_ = from_
80 self.to = to
83@_display_as_base
84class _UFuncInputCastingError(_UFuncCastingError):
85 """ Thrown when a ufunc input cannot be casted """
86 def __init__(self, ufunc, casting, from_, to, i):
87 super().__init__(ufunc, casting, from_, to)
88 self.in_i = i
90 def __str__(self):
91 # only show the number if more than one input exists
92 i_str = "{} ".format(self.in_i) if self.ufunc.nin != 1 else ""
93 return (
94 "Cannot cast ufunc {!r} input {}from {!r} to {!r} with casting "
95 "rule {!r}"
96 ).format(
97 self.ufunc.__name__, i_str, self.from_, self.to, self.casting
98 )
101@_display_as_base
102class _UFuncOutputCastingError(_UFuncCastingError):
103 """ Thrown when a ufunc output cannot be casted """
104 def __init__(self, ufunc, casting, from_, to, i):
105 super().__init__(ufunc, casting, from_, to)
106 self.out_i = i
108 def __str__(self):
109 # only show the number if more than one output exists
110 i_str = "{} ".format(self.out_i) if self.ufunc.nout != 1 else ""
111 return (
112 "Cannot cast ufunc {!r} output {}from {!r} to {!r} with casting "
113 "rule {!r}"
114 ).format(
115 self.ufunc.__name__, i_str, self.from_, self.to, self.casting
116 )
119# Exception used in shares_memory()
120@set_module('numpy')
121class TooHardError(RuntimeError):
122 pass
125@set_module('numpy')
126class AxisError(ValueError, IndexError):
127 """ Axis supplied was invalid. """
128 def __init__(self, axis, ndim=None, msg_prefix=None):
129 # single-argument form just delegates to base class
130 if ndim is None and msg_prefix is None:
131 msg = axis
133 # do the string formatting here, to save work in the C code
134 else:
135 msg = ("axis {} is out of bounds for array of dimension {}"
136 .format(axis, ndim))
137 if msg_prefix is not None:
138 msg = "{}: {}".format(msg_prefix, msg)
140 super(AxisError, self).__init__(msg)
143@_display_as_base
144class _ArrayMemoryError(MemoryError):
145 """ Thrown when an array cannot be allocated"""
146 def __init__(self, shape, dtype):
147 self.shape = shape
148 self.dtype = dtype
150 @property
151 def _total_size(self):
152 num_bytes = self.dtype.itemsize
153 for dim in self.shape:
154 num_bytes *= dim
155 return num_bytes
157 @staticmethod
158 def _size_to_string(num_bytes):
159 """ Convert a number of bytes into a binary size string """
161 # https://en.wikipedia.org/wiki/Binary_prefix
162 LOG2_STEP = 10
163 STEP = 1024
164 units = ['bytes', 'KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB']
166 unit_i = max(num_bytes.bit_length() - 1, 1) // LOG2_STEP
167 unit_val = 1 << (unit_i * LOG2_STEP)
168 n_units = num_bytes / unit_val
169 del unit_val
171 # ensure we pick a unit that is correct after rounding
172 if round(n_units) == STEP:
173 unit_i += 1
174 n_units /= STEP
176 # deal with sizes so large that we don't have units for them
177 if unit_i >= len(units):
178 new_unit_i = len(units) - 1
179 n_units *= 1 << ((unit_i - new_unit_i) * LOG2_STEP)
180 unit_i = new_unit_i
182 unit_name = units[unit_i]
183 # format with a sensible number of digits
184 if unit_i == 0:
185 # no decimal point on bytes
186 return '{:.0f} {}'.format(n_units, unit_name)
187 elif round(n_units) < 1000:
188 # 3 significant figures, if none are dropped to the left of the .
189 return '{:#.3g} {}'.format(n_units, unit_name)
190 else:
191 # just give all the digits otherwise
192 return '{:#.0f} {}'.format(n_units, unit_name)
194 def __str__(self):
195 size_str = self._size_to_string(self._total_size)
196 return (
197 "Unable to allocate {} for an array with shape {} and data type {}"
198 .format(size_str, self.shape, self.dtype)
199 )