Question

This bothers me a bit:

Suppose you have a matrix with three layers.

Is there a simple way to multiply this matrix with a vector of three elements so that the first layer (all elements) gets multiplied with the first element of the vector and so on…

Now I have to use a function to do it like this:

function out=fun(matrix,vector)

out=matrix;
for k=1:3
    out(:,:,k)=out(:,:,k)*vector(k);
end

Is there a efficient way to do this in just one line without the need for a function?

Answer 1

One very terse solution is to reshape vector into a 1-by-1-by-3 matrix and use the function BSXFUN to perform the element-wise multiplication (it will replicate dimensions as needed to match the sizes of the two input arguments):

newMatrix = bsxfun(@times,matrix,reshape(vector,[1 1 3]));