2b462d8665
Former-commit-id:06a8b51d6d[formerlya02aeb236c[formerly9f19e3f712] [formerly06a8b51d6d[formerly 64fa9254b946eae7e61bbc3f513b7c3696c4f54f]]] Former-commit-id:a02aeb236c[formerly9f19e3f712] Former-commit-id:a02aeb236cFormer-commit-id:133dc97f67
50 lines
1.4 KiB
Python
Executable file
50 lines
1.4 KiB
Python
Executable file
# A nicer way to build up index tuples for arrays.
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#
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# You can do all this with slice() plus a few special objects,
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# but there's a lot to remember. This version is simpler because
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# it uses the standard array indexing syntax.
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#
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# Written by Konrad Hinsen <hinsen@cnrs-orleans.fr>
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# last revision: 2006-6-12
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#
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"""
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Array indexing utility
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This module provides a convenient method for constructing
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array indices algorithmically. It provides one importable object,
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L{index_expression}.
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For any index combination, including slicing and axis insertion,
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C{a[indices]} is the same as C{a[index_expression[indices]]} for any
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array {a}. However, C{index_expression[indices]} can be used anywhere
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in Python code and returns a tuple of indexing objects that can be
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used in the construction of complex index expressions.
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Sole restriction: Slices must be specified in the double-colon
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form, i.e. C{a[::]} is allowed, whereas C{a[:]} is not.
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"""
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class _index_expression_class:
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import sys
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maxint = sys.maxint
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def __init__(self):
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pass
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def __getitem__(self, item):
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if type(item) != type(()):
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return (item,)
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else:
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return item
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def __len__(self):
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return self.maxint
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def __getslice__(self, start, stop):
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if stop == self.maxint:
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stop = None
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return self[start:stop:None]
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index_expression = _index_expression_class()
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