a = [1,2,3] b = ['a','b','c'] c = [1,2,3] d = ['a','b','c'] print(dict(zip(a,b))) #{1: 'a', 2: 'b', 3: 'c'} print(list(zip(a,b))) # [(1, 'a'), (2, 'b'), (3, 'c')]
filter(function or None, iterable) 遍历可迭代对象,过滤符合要求的值
c = [-10, 28, 9, -5, 30, 5] print(list(filter(lambda a:a>0, c)))
map(function or None, iterable) 遍历可迭代对象,每个值作用到函数,返回一个列表
c = [-10, 28, 9, -5, 30, 5] print(list(map(lambda a:a>0, c)))
educe() 函数表示对参数序列中所有元素进行累积
print (reduce(lambda x,y:x+y, range(1, 101))) # 计算1-100的值
5.map和filter的却别
def only_int(x): try: if isinstance(x, int): return True else: return False except ValueError as e: return False dt1 = filter(only_int, [1, 2, 3, 3, '3232', -34.5, 34.5]) print(list(dt1)) #[1, 2, 3, 3] dt2 = map(only_int, [1, 2, 3, 3, '3232', -34.5, 34.5]) print(list(dt2)) # [True, True, True, True, False, False, False]