def filter(self, **kwargs):
"""
filters the sequence based on a set of criteria. Parameter
names should be equivalent to the properties accessible in the items
of the sequence. For example, where the items are instances of
the Stats class::
players.filter(home=True, passing_tds=1, rushing_yds=lambda x: x>0)
Returns a sequence with only players on the home team that
have a single passing touchdown and more than zero rushing yards.
If a field specified does not exist for a particular item, that
item is excluded from the result set.
If a field is set to a value, then only items with fields that equal
that value are returned.
If a field is set to a function---which must be a predicate---then
only items with field values satisfying that function will
be returned.
Also, special suffixes that begin with '__' may be added to the
end of a field name to invoke built in predicates.
For example, this::
players.filter(receiving_rec=lambda v: v > 0)
Is equivalent to::
players.filter(receiving_rec__gt=0)
Other suffixes includes gt, le, lt, ne, ge, etc.
(Django users should feel right at home.)
"""
preds = []
for k, v in iteritems(kwargs):
def pred(field, value, item):
# TODO: Move pred function outside of loop
for suffix, p in iteritems(_BUILTIN_PREDS):
if field.endswith(suffix):
f = field[:field.index(suffix)]
if not hasattr(item, f) or getattr(item, f) is None:
return False
return p(getattr(item, f), value)
if not hasattr(item, field) or getattr(item, field) is None:
return False
if isinstance(value, type(lambda x: x)):
return value(getattr(item, field))
return getattr(item, field) == value
preds.append(functools.partial(pred, k, v))
gen = ifilter(lambda item: all([f(item) for f in preds]), self)
return self.__class__(gen)
def filter(self, **kwargs):
"""
filters the sequence based on a set of criteria. Parameter
names should be equivalent to the properties accessible in the items
of the sequence. For example, where the items are instances of
the Stats class::
players.filter(home=True, passing_tds=1, rushing_yds=lambda x: x>0)
Returns a sequence with only players on the home team that
have a single passing touchdown and more than zero rushing yards.
If a field specified does not exist for a particular item, that
item is excluded from the result set.
If a field is set to a value, then only items with fields that equal
that value are returned.
If a field is set to a function---which must be a predicate---then
only items with field values satisfying that function will
be returned.
Also, special suffixes that begin with '__' may be added to the
end of a field name to invoke built in predicates.
For example, this::
players.filter(receiving_rec=lambda v: v > 0)
Is equivalent to::
players.filter(receiving_rec__gt=0)
Other suffixes includes gt, le, lt, ne, ge, etc.
(Django users should feel right at home.)
"""
preds = []
for k, v in iteritems(kwargs):
def pred(field, value, item):
# TODO: Move pred function outside of loop
for suffix, p in iteritems(_BUILTIN_PREDS):
if field.endswith(suffix):
f = field[:field.index(suffix)]
if not hasattr(item, f) or getattr(item, f) is None:
return False
return p(getattr(item, f), value)
if not hasattr(item, field) or getattr(item, field) is None:
return False
if isinstance(value, type(lambda x: x)):
return value(getattr(item, field))
return getattr(item, field) == value
preds.append(functools.partial(pred, k, v))
gen = ifilter(lambda item: all([f(item) for f in preds]), self)
return self.__class__(gen)
def __filter_category(self, cat):
return self.__class__(ifilter(lambda p: p.has_cat(cat), self))
def __filter_category(self, cat):
return self.__class__(ifilter(lambda p: p.has_cat(cat), self))
