when using function 'activations', error shows'The dimensions of the array to be concatenated are not consistent.'

I have a trained nerual network. I need to know how well it works and I used 'activations', I have check the documention of the function and it saied that in the format

"b = activations(net,a,'regressionlayer')", a's size can be bigger than the input size of the net.

I have no idea how to solve this error, please help.

Answer 1

[Chuan Yu]

I've solved this problem myself. I found that there are many other variables in my net.mat besides the net, which causes the problem.