def test_itemfilter(self):
D, kw = self.D, self.kw
assert itemfilter(lambda item: iseven(item[0]), D({
1: 2,
2: 3
}), **kw) == D({2: 3})
assert itemfilter(lambda item: iseven(item[1]), D({
1: 2,
2: 3
}), **kw) == D({1: 2})
def valid_dict(d, keys=None):
"""
检查是否字典中含有值为None的键(给定键的名称则检查给定的键，如果没有，则检查全部键)
- 如果没有值为None的键，则返回True，反之False
- 如果keys中的键不存在于d中，也返回False
"""
if keys is None:
d_ = d
else:
d_ = itemfilter(lambda item: item[0] in keys, d)
if len(d_) != len(keys):
return False
values = list(itervalues(d_))
return False if None in values else True
def test_itemfilter(self):
D, kw = self.D, self.kw
assert itemfilter(lambda item: iseven(item[0]), D({1: 2, 2: 3}), **kw) == D({2: 3})
assert itemfilter(lambda item: iseven(item[1]), D({1: 2, 2: 3}), **kw) == D({1: 2})
def filter(self, f: Callable[[Tuple[A, B]], bool]) -> 'Map[A, B]':
return Map(dicttoolz.itemfilter(f, self))
def test_itemfilter():
assert itemfilter(lambda item: iseven(item[0]), {1: 2, 2: 3}) == {2: 3}
assert itemfilter(lambda item: iseven(item[1]), {1: 2, 2: 3}) == {1: 2}
# #pip3 install itertoolz
#
# python3 demo.py
# Now included since Python 3.
#from itertoolz import filterfalse
from itertools import filterfalse
# See installation steps above.
from toolz.dicttoolz import keyfilter, valfilter, itemfilter
def is_even(x):
if x % 2 == 0: return True
else: return False
def both_are_even(x):
k, v = x
if is_even(k) and is_even(v): return True
else: return False
print(list(filter(is_even, range(10))))
print(list(filterfalse(is_even, range(10))))
# Note: If we wrap these with a "list()" call then we don't print items, i.e. x:y
print(keyfilter(is_even, {1: 2, 2: 3, 3: 4, 4: 5, 5: 6}))
print(valfilter(is_even, {1: 2, 2: 3, 3: 4, 4: 5, 5: 6}))
print(itemfilter(both_are_even, {1: 5, 2: 4, 3: 3, 4: 2, 5: 1}))
def filter(self, f: Callable[[Tuple[A, B]], bool]) -> 'Map[A, B]':
return Map(dicttoolz.itemfilter(f, self))
def test_itemfilter():
assert itemfilter(lambda item: iseven(item[0]), {1: 2, 2: 3}) == {2: 3}
assert itemfilter(lambda item: iseven(item[1]), {1: 2, 2: 3}) == {1: 2}