37 lines
1.1 KiB
Python
37 lines
1.1 KiB
Python
|
# encoding: utf-8
|
||
|
|
"""Utilities for working with data structures like lists, dicts and tuples.
|
||
|
|
"""
|
||
|
|
|
||
|
|
#-----------------------------------------------------------------------------
|
||
|
|
# Copyright (C) 2008-2011 The yap_ipython Development Team
|
||
|
|
#
|
||
|
|
# Distributed under the terms of the BSD License. The full license is in
|
||
|
|
# the file COPYING, distributed as part of this software.
|
||
|
|
#-----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
|
||
|
|
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.
|
||
|
|
|
||
|
|
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)]
|
||
|
|
|
||
|
|
|
||
|
|
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]
|
||
|
|
|
||
|
|
|
||
|
|
def chop(seq, size):
|
||
|
|
"""Chop a sequence into chunks of the given size."""
|
||
|
|
return [seq[i:i+size] for i in range(0,len(seq),size)]
|
||
|
|
|
||
|
|
|