Question

我正在使用ipython脚本下的python3.7在Anaconda中尝试神经网络前馈。

我不熟悉，仍然在学习python的问题，并且不知道如何调试它。

import numpy as np
w1 = np.array([[11, 11, 9, 11, 7,13, 14, 6, 6, 12], [11, 11, 9, 11, 7,13, 14, 6, 6, 12], [11, 11, 9, 11, 7,13, 14, 6, 6, 12]])
w2 = np.zeros ((1,10))
b1 = np.array([0.8, 0.8, 0.8, 0.8, 0.8, 0.8, 0.8, 0.8, 0.8, 0.8])
b2 = np.array([0.2])
def f(x):
        return 1 / (1 + np.exp(-x))
def simple_looped_nn_calc(n_layers, x,w,b):
  for l in range(n_layers-1):
    if l == 0:
         node_in = x
    else:
         node_in = h
    h = np.zeros((w[l].shape[0],))
    for i in range(w[l].shape[0]):
       f_sum = 0
       for j in range(w[l].shape[l]):
            f_sum += w[l][i][j]* node_in[j]
       f_sum += b[l][i]
       h[i] = f(f_sum)
  return h



w = [w1, w2]
b = [b1, b2]
x = [280, 0, 280, 280, 0, 0, 0, 0, 280, 0, 0, 0, 0, 0, 0, 0, 0, 280, 0]

当我运行代码时，出现如下错误：simple_looped_nn_calc（3，x，w，b）：

IndexError：索引3超出了大小为3的轴0的边界

Answer 1

确定要写：

for j in range(w[l].shape[l]):

不是

for j in range(w[l].shape[1]):

希望我能帮上忙！

Answer 2

替换

for j in range(w[l].shape[l])

与

for j in range(w[l].shape[0])

因为您要分配node_in = h，所以h是h = np.zeros((w[l].shape[0],))，所以如果您要进行for i in range(w[l].shape[l])，则node_in和w[l].shape[l]的大小可能不匹配，并且会导致索引错误。

python IndexError：索引3超出轴3的大小3

2 个答案: