本文整理汇总了Python中collections.Counter.__sub__方法的典型用法代码示例。如果您正苦于以下问题：Python Counter.__sub__方法的具体用法？Python Counter.__sub__怎么用？Python Counter.__sub__使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类collections.Counter的用法示例。
在下文中一共展示了Counter.__sub__方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: test_inplace_operations
# 需要导入模块: from collections import Counter [as 别名]
# 或者: from collections.Counter import __sub__ [as 别名]
def test_inplace_operations(self):
elements = 'abcd'
for i in range(1000):
# test random pairs of multisets
p = Counter(dict((elem, randrange(-2,4)) for elem in elements))
p.update(e=1, f=-1, g=0)
q = Counter(dict((elem, randrange(-2,4)) for elem in elements))
q.update(h=1, i=-1, j=0)
for inplace_op, regular_op in [
(Counter.__iadd__, Counter.__add__),
(Counter.__isub__, Counter.__sub__),
(Counter.__ior__, Counter.__or__),
(Counter.__iand__, Counter.__and__),
]:
c = p.copy()
c_id = id(c)
regular_result = regular_op(c, q)
inplace_result = inplace_op(c, q)
self.assertEqual(inplace_result, regular_result)
self.assertEqual(id(inplace_result), c_id) 示例2: test_multiset_operations
# 需要导入模块: from collections import Counter [as 别名]
# 或者: from collections.Counter import __sub__ [as 别名]
def test_multiset_operations(self):
# Verify that adding a zero counter will strip zeros and negatives
c = Counter(a=10, b=-2, c=0) + Counter()
self.assertEqual(dict(c), dict(a=10))
elements = 'abcd'
for i in range(1000):
# test random pairs of multisets
p = Counter(dict((elem, randrange(-2,4)) for elem in elements))
p.update(e=1, f=-1, g=0)
q = Counter(dict((elem, randrange(-2,4)) for elem in elements))
q.update(h=1, i=-1, j=0)
for counterop, numberop in [
(Counter.__add__, lambda x, y: max(0, x+y)),
(Counter.__sub__, lambda x, y: max(0, x-y)),
(Counter.__or__, lambda x, y: max(0,x,y)),
(Counter.__and__, lambda x, y: max(0, min(x,y))),
]:
result = counterop(p, q)
for x in elements:
self.assertEqual(numberop(p[x], q[x]), result[x],
(counterop, x, p, q))
# verify that results exclude non-positive counts
self.assertTrue(x>0 for x in result.values())
elements = 'abcdef'
for i in range(100):
# verify that random multisets with no repeats are exactly like sets
p = Counter(dict((elem, randrange(0, 2)) for elem in elements))
q = Counter(dict((elem, randrange(0, 2)) for elem in elements))
for counterop, setop in [
(Counter.__sub__, set.__sub__),
(Counter.__or__, set.__or__),
(Counter.__and__, set.__and__),
]:
counter_result = counterop(p, q)
set_result = setop(set(p.elements()), set(q.elements()))
self.assertEqual(counter_result, dict.fromkeys(set_result, 1))