I want to simply subtract 2 matrices with size 784×1 with this code

w2 = G.w - alpha *temp
print(w2.size)

but w2 is a 784×784 matrix. why doesn't element-wise subtraction work properly? both temp and G.w are 784×1 matrices and alpha is a scalar (alpha = 0.1) I'm using pycharm on windows 10. rethink about creating G.w and temp