python reduce函数 day16
首先从功能模块中导入函数
from functools import reduce
要实现的功能
num_1 = [1,2,3,4,5,6,100] # res = 0 # for num in num_1: # res +=num # print (res) # # def reduce_test(array): # res = 0 # for num in array: # res+=num # return res # print(reduce_test(num_1))
实现代码
# from functools import reduce num_1 = [1,2,3,4,5,6,100] def reduce_test(func,array): res = array.pop(0) for num in array: res=func(res,num) return res # print(reduce_test(num_1)) print(reduce_test(lambda x,y:x*y,num_1))
# from functools import reduce num_1 = [1,2,3,4,5,6,100] def reduce_test(func,array,init=None): if init is None: res = array.pop(0) else: res = init for num in array: res=func(res,num) return res # print(reduce_test(num_1)) print(reduce_test(lambda x,y:x*y,num_1,0))
reduce将所有元素运算行成一个数,公式,列表,默认值