Element wise (.*) in Simulink for two matrices with different dimensions

Let Anxm and Bnx1 be two matrices with different dimensions

On Matlab: element-wise multiplication ie. A.*B = a Cnxm Matrix with no errors.

Example:

[1 2 3; 4 5 6;] .* [1; 0] = [1 2 3; 0 0 0]

However on Simulink If I use the Product block set on element-wise multiplication on A and B I get mismatch widths or dimensions Error.

Note that If I used a Matlab function Block on Simulink that calls A.*B. I am able to get the result I need. but I am looking for a solution that does not use the matlab function Block. Please share any solution you might think of.

Thanks!

Answer 1

[Fangjun Jiang]

a=[1 2 3; 4 5 6];
b=[1; 0];
a.*b

ans = 2×3

1 2 3 0 0 0

This is a change made in MATLAB in R2016b when implicit expansion is introduced. Prior to R2016b, it will cause a "size mismatch" error.

Simulink does not have similar change to make it be supported by its blocks, as far as R2022b.

To make a block diagram work, and with your existing data "b", you will have to expand it yourself through another block

c=ones(1,3);
a.*(b*c)

ans = 2×3

1 2 3 0 0 0