python - 如何在 Python 的同一公式中使用列表列表的元素？

Question

我需要在同一公式中使用列表列表中的元素

import math

def equate(A):
    n = len[A]
    sum = 0
    for i in A:
        sum = sum + ((A[i] * math.log10(A[j]) + (1-A[i] * math.log10(1 - A[j]))
    loss = -1/n * sum
    return loss

A = [[1, 0.4], [0, 0.5], [0, 0.9], [0, 0.3], [0, 0.6], [1, 0.1], [1, 0.9], [1, 0.8]]
Answer = equate(A)
print(Answer)

低于错误

File "/home/988659d072a77d5e9b58fa933c5d006f.py", line 7

loss = -1/n * sum
   ^

SyntaxError: invalid syntax

标签： pythonnested-lists

Answer 1

你少了一个括号。

sum = sum + ((A[i] * math.log10(A[j]) + (1-A[i] * math.log10(1 - A[j]))) 
# Missing a parenthesis at the end.