98 lines
3.7 KiB
Python
98 lines
3.7 KiB
Python
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# Copyright (C) 2003-2005 Peter J. Verveer
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions
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# are met:
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#
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# 1. Redistributions of source code must retain the above copyright
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# notice, this list of conditions and the following disclaimer.
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#
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# 2. Redistributions in binary form must reproduce the above
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# copyright notice, this list of conditions and the following
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# disclaimer in the documentation and/or other materials provided
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# with the distribution.
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#
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# 3. The name of the author may not be used to endorse or promote
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# products derived from this software without specific prior
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# written permission.
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#
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# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
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# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
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# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
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# GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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from collections.abc import Iterable
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import warnings
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import numpy
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def _extend_mode_to_code(mode):
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"""Convert an extension mode to the corresponding integer code.
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"""
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if mode == 'nearest':
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return 0
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elif mode == 'wrap':
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return 1
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elif mode in ['reflect', 'grid-mirror']:
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return 2
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elif mode == 'mirror':
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return 3
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elif mode == 'constant':
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return 4
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elif mode == 'grid-wrap':
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return 5
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elif mode == 'grid-constant':
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return 6
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else:
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raise RuntimeError('boundary mode not supported')
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def _normalize_sequence(input, rank):
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"""If input is a scalar, create a sequence of length equal to the
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rank by duplicating the input. If input is a sequence,
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check if its length is equal to the length of array.
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"""
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is_str = isinstance(input, str)
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if not is_str and isinstance(input, Iterable):
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normalized = list(input)
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if len(normalized) != rank:
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err = "sequence argument must have length equal to input rank"
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raise RuntimeError(err)
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else:
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normalized = [input] * rank
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return normalized
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def _get_output(output, input, shape=None, complex_output=False):
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if shape is None:
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shape = input.shape
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if output is None:
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if not complex_output:
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output = numpy.zeros(shape, dtype=input.dtype.name)
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else:
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complex_type = numpy.promote_types(input.dtype, numpy.complex64)
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output = numpy.zeros(shape, dtype=complex_type)
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elif isinstance(output, (type, numpy.dtype)):
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# Classes (like `np.float32`) and dtypes are interpreted as dtype
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if complex_output and numpy.dtype(output).kind != 'c':
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warnings.warn("promoting specified output dtype to complex")
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output = numpy.promote_types(output, numpy.complex64)
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output = numpy.zeros(shape, dtype=output)
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elif isinstance(output, str):
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output = numpy.sctypeDict[output]
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if complex_output and numpy.dtype(output).kind != 'c':
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raise RuntimeError("output must have complex dtype")
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output = numpy.zeros(shape, dtype=output)
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elif output.shape != shape:
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raise RuntimeError("output shape not correct")
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elif complex_output and output.dtype.kind != 'c':
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raise RuntimeError("output must have complex dtype")
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return output
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