cascading mux blocks syntax help needed

In simulink I have a mux block leading into the first signal of a second mux block which leads into a function block. In the function block, what is the syntax to reference one of the signals from the first mux block? Currently I have u[1[3]].

Answer 1

[Sebastian Castro]

Two issues here:

• If you look at the example syntax right above where you typed, you need to use MATLAB-style indexing with parentheses. So you want u(1) instead of u[1], for instance.
• Simulink muxes do not implement "nesting"; instead, they stack all signals vertically. In your example, the output of the second Mux should simply be a 4-element array.

By the way, if all you want to do with that Fcn block is extract individual elements of a multidimensional signal, you can also use the Selector block.

Sebastian

[Kelsey Thompson]

So the corrected statement would look like u(2)*u(1,3) ?

[Sebastian Castro]

Did you try that, and did it work?

I think the corrected statement would be u(4)*u(3), since -- as I mentioned -- muxes don't nest but rather stack things into one big vector.

Again, there's no harm in trying this out yourself and seeing what works :)

[Kelsey Thompson]

Your suggestion worked. Thanks for the help!