在这里浏览了流行的神经网络教程之后: https://www.youtube.com/watch?v=h3l4qz76JhQ
我相信我已经完全按照本教程进行了学习,但是结果如下:
Error:0.496410031903
Error:0.499999652828
Error:0.499999831726
Error:0.49999988989
Error:0.499999918514
Error:0.499999935488
Output after training:
[[ 0.50000107]
[ 0.50000133]
[ 0.50000142]
[ 0.50000147]]
这与Siraj的完美输出相差甚远
这是我的代码:
def nonlin(x, deriv=False):
if (deriv == True):
return x*(1-x)
return 1/(1+np.exp(-x))
X = np.array([[0,0,1],[0,1,1],[1,0,1],[1,1,1]])
y = np.array([[0],[1],[1],[0]])
np.random.seed(1)
syn0 = 2*np.random.random((3,4)) - 1
syn1 = 2*np.random.random((4,1)) - 1
for j in range(60000):
l0 = X
l1 = nonlin(np.dot(l0, syn0))
l2 = nonlin(np.dot(l1, syn1))
l2_error = y - l2
if (j % 10000 == 0):
print("Error:" + str(np.mean(np.abs(l2_error))))
l2_delta = l2_error*nonlin(l2, deriv=True)
l1_error = l2_delta.dot(syn1.T)
l1_delta = l1_error + nonlin(l1, deriv=True)
# update weights
syn1 += l1.T.dot(l2_delta)
syn0 += l0.T.dot(l1_delta)
print("Output after training:")
print(l2)
我在评估函数中是否犯了错误,我是否停留在局部最小值上,反向传播部分是否错误,本教程是否错误?