def _position_filter(mask):
'''generate a filter for a position mask (dict, set, or where)'''
if mask is None:
pairs = False # the default format
selector = lambda x: x
elif type(mask) is set:
import itertools
_zip = getattr(itertools, 'izip', zip)
if mask:
from mystic.tools import _inverted
_mask, pairs = _zip(*mask)
_mask = set(_zip(_mask, _inverted(pairs)))
else:
_mask = mask
pairs = True
selector = lambda x: x - mask - _mask
elif type(mask) is dict:
pairs = False
from mystic.tools import _symmetric
selector = lambda x: dict((k, v) for (k, v) in (
(i, j - _symmetric((mask[i] if i in mask else set())))
for (i, j) in getattr(x, 'iteritems', x.items)()) if v)
else:
import itertools
from mystic.tools import _inverted
_zip = getattr(itertools, 'izip', zip)
_mask, pairs = mask
mask = _mask + _mask, tuple(pairs) + tuple(_inverted(pairs))
pairs = None #XXX: special case, use where notation
selector = lambda x: tuple(
_zip(*(i for i in _zip(*x) if i not in _zip(*mask)))
) #FIXME: searching set would be faster
return selector, pairs
def _position_filter(mask):
'''generate a filter for a position mask (dict, set, or where)'''
if mask is None:
pairs = False # the default format
selector = lambda x: x
elif type(mask) is set:
import itertools
_zip = getattr(itertools, 'izip', zip)
if mask:
from mystic.tools import _inverted
_mask,pairs = _zip(*mask)
_mask = set(_zip(_mask,_inverted(pairs)))
else: _mask = mask
pairs = True
selector = lambda x: x - mask - _mask
elif type(mask) is dict:
pairs = False
from mystic.tools import _symmetric
selector = lambda x: dict((k,v) for (k,v) in ((i,j - _symmetric((mask[i] if i in mask else set()))) for (i,j) in getattr(x, 'iteritems', x.items)()) if v)
else:
import itertools
from mystic.tools import _inverted
_zip = getattr(itertools, 'izip', zip)
_mask,pairs = mask
mask = _mask+_mask, tuple(pairs)+tuple(_inverted(pairs))
pairs = None #XXX: special case, use where notation
selector = lambda x: tuple(_zip(*(i for i in _zip(*x) if i not in _zip(*mask)))) #FIXME: searching set would be faster
return selector, pairs