MATLAB: How to take the non zero values from one matrix and put them in another?

Question

I have a matrix [640 640] with few non zero values and many zeros. I want to put all the non zero values in a new matrix. Something like:

for i=1:640

 for j=1:640
if A(i,j)~=0
B(i,j)=A(i,j)
   end

end

end

But this doesn't work.. Any suggestions?

Answer 1

    B=A(A~=0);