lambda用法

1 lambda_add_ten = lambda x: x + 1
2 print(lambda_add_ten(6)) # 7
3 print((lambda x, y: x if x>y else y)(1,2)) # 2

1 foo = [1,2,3,4]
2 print(list(filter(lambda x: x % 2 == 0, foo))) #过滤 [2, 4]
3 print(list(map(lambda x: x + 2, foo)))         #映射 [3, 4, 5, 6]
4 print(reduce(lambda x, y: x + y, foo))         #累积 10

1 info = [('(Michael Jordan',60), ('James',38), ('Kobe Bryant',42)]
2 print(sorted(info, key=lambda age:age[1]))  # 按照第二个元素，索引为1排序 [('James', 38), ('Kobe Bryant', 42), ('(Michael Jordan', 60)]