data.py
37 lines
| 1.2 KiB
| text/x-python
|
PythonLexer
Brian Granger
|
r2498 | # encoding: utf-8 | ||
| """Utilities for working with data structures like lists, dicts and tuples. | ||||
| """ | ||||
| #----------------------------------------------------------------------------- | ||||
Matthias BUSSONNIER
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r5390 | # Copyright (C) 2008-2011 The IPython Development Team | ||
|
Brian Granger
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r2498 | # | ||
| # Distributed under the terms of the BSD License. The full license is in | ||||
| # the file COPYING, distributed as part of this software. | ||||
| #----------------------------------------------------------------------------- | ||||
Thomas Kluyver
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r13356 | from .py3compat import xrange | ||
|
Brian Granger
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r2498 | def uniq_stable(elems): | ||
| """uniq_stable(elems) -> list | ||||
| Return from an iterable, a list of all the unique elements in the input, | ||||
| but maintaining the order in which they first appear. | ||||
W. Trevor King
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r9249 | Note: All elements in the input must be hashable for this routine | ||
| to work, as it internally uses a set for efficiency reasons. | ||||
| """ | ||||
| seen = set() | ||||
| return [x for x in elems if x not in seen and not seen.add(x)] | ||||
|
Brian Granger
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r2498 | |||
| def flatten(seq): | ||||
| """Flatten a list of lists (NOT recursive, only works for 2d lists).""" | ||||
| return [x for subseq in seq for x in subseq] | ||||
|
Thomas Kluyver
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r9471 | |||
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Brian Granger
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r2498 | |||
| def chop(seq, size): | ||||
| """Chop a sequence into chunks of the given size.""" | ||||
|
Thomas Kluyver
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r9471 | return [seq[i:i+size] for i in xrange(0,len(seq),size)] | ||
|
Brian Granger
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r2498 | |||