How can variables in workspace be used in Simulink function

Let say we have a variable defined in workspace

ax=10

I want to use this variable in a Simulink function "abc" defined as:

function y = abc(u) 
y=ax*u;
end

Why simulink is showing me an error while executing this function. Alternatively, I used to declare the variable as:

global ax

but it doesn't work.

Can someone help me to solve this issue?

Answer 1

[KL]

One idea is to take it as an input to your function block and use the "constant block".

Your function could look like,

 function y = abc(ax,u) 
 y=ax*u;
 end

Enter ax as the value in your constant block and no need to define it as global.

[Drill Be]

Dear,

Yes, you are right, but I have a huge scheme in Simulink and it is not a convenient manner. There should be a solution for such situation.

[KL]

Well, If you explain more about your actual problem, it would be easier to find if there's any alternatives to global variables but anyway, using global variables inside matlab function block in simulink is explained in this documentation here.

https://www.mathworks.com/help/releases/R2011b/toolbox/simulink/ug/bsds2rv.html

But be warned about the dangers come with using global variables. If you have a huge scheme, it only gets worse.

https://www.mathworks.com/matlabcentral/answers/351423-problem-with-global-variables