Error while using Input + Weight Vectorised Version of 0328 Vectorized Feed Forward Networks file

Could you print the input shapes

Please reshape Y_train to (-1,1), if it is not

I tried your notebook, and generated random numbers for X and Y where Y’s dimension was (63,)
As a result, the first step in backprop i.e self.dA2 = self.H2 - Y gives an output of (63,63) instead of (63,1) due to broadcasting operation.

It would work well if Y was of shape (63,1)


Inside class FF_MultiClass_InputWeightVectorised,
change the following inside grad function.

self.dA2 = self.H2 - Y


self.dA2 = self.H2 - Y.reshape(-1, 1)

Right now, Y is 1-dim and you need to force it to a 2-d with 1 column otherwise automatic broadcast will make the operation incorrect.

Just noticed, I just duplicated what @databaaz wrote in his reply :slight_smile: