Limnoria/src/utils/seq.py

###
# Copyright (c) 2002-2005, Jeremiah Fincher
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###

def window(L, size):
    """list * size -> window iterable

    Returns a sliding 'window' through the list L of size size."""
    assert not isinstance(L, int), 'Argument order swapped: window(L, size)'
    if size < 1:
        raise ValueError, 'size <= 0 disallowed.'
    for i in xrange(len(L) - (size-1)):
        yield L[i:i+size]

def mapinto(f, L):
    for (i, x) in enumerate(L):
        L[i] = f(x)

def renumerate(L):
    for i in xrange(len(L)-1, -1, -1):
        yield (i, L[i])



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