im试图为i和j的每个组合应用函数$ y =(x_i-x_j)$。并且j,i = {1,2,...,5}和x = {10,-15,13,20,-4}。例如,对于i = 1和j = 1,我们有y = x_1-x_1 = 0。现在对于i = 1和j = 2,我们有y = x_2-x_1 = 25
我尝试过for循环,但我不知道如何使其像矩阵一样
y=[]
for k in range(0,4)
for j in range (0,4)
y.append(x[k]-x[j])
但是无法按照我的要求工作。你们能帮我一下吗。谢谢
此作品:
import pprint
x_in = [10, -15, 13, 20, -4]
matrix = [[[0] for i in range(len(x_in))] for i in range(len(x_in))]
for i, x1 in enumerate(x_in):
for j, x2 in enumerate(x_in):
matrix[j][i] = x1 - x2
pprint.pprint(matrix)
输出:
[[0, -25, 3, 10, -14],
[25, 0, 28, 35, 11],
[-3, -28, 0, 7, -17],
[-10, -35, -7, 0, -24],
[14, -11, 17, 24, 0]]