Using kronecker product and elementwise multiplication

Dear all,

I have the matrix

 der=[2 5 ;3 4]
 OMEGA=kron(eye(2),der);

Suppose that now I have the 1 by 2 vector y

 y=[3 4];

I want to multiply the first element of y with the first 'der' which is with OMEGA and the second element of y with the second 'der' which is within OMEGA.

Any ideas? Thanks in advance

Answer 1

[James Tursa]

yy = repmat(y,size(der,1),1);
result = bsxfun(@times,OMEGA,yy(:));

or in later versions of MATLAB

result = OMEGA .* yy(:);

Should work even if der is not square.

Answer 2

[Andrei Bobrov]

der=[2 5 ;3 4]
OMEGA=kron(eye(2),der)
y=[3 4]

out = OMEGA.*kron(y,ones(1,2))