How do I call an anonymous function inside the MATLAB function block in Simulink 8.1 (R2013a)?

I have a model which has the MATLAB function block. I want to be able to call the FMINBND anonymous function within this block.I understand that this is a function that is not within the list of supported functions for the MATLAB function block and so I use coder.extrinsic to declare FMINBND as follows:

function y = fcn()
%#codegen

coder.extrinsic('fminbnd')
y = fminbnd(@(x) x.^2+100-650, 0, 100);

end

However, I get the following error when I run the model:

This kind of expression is not supported.

How do I get around this?

Answer 1

[MathWorks Support Team]

Embedded MATLAB does not support anonymous functions, as documented in the documentation page "MATLAB Language Features Supported for C/C++ Code Generation":

>>web([docroot '/simulink/ug/matlab-language-features-supported-for-code-generation.html']) 

However, you can workaround the issue by creating a seperate MATLAB function, say myFunc.m, that calls the anonymous function FMINBND and then using coder.extrinsic to declare this myFunc.m and use it. This is illustrated in the example code below:

function y = fcn()
%#codegen
y = 0;
coder.extrinsic('myFunc')
y = myFunc();
end

Where myFunc.m is:

function a = myFunc()
a =fminbnd(@(x) x.^2+100-650, 0, 100);
end

Answer 2

[Walter Roberson]

If sum(q) == 0 because all of the entries are 0, then you only store into Q(1) and none of the other locations in Q.

Remember that the first assignment to a variable determines the size of the variable, so the first thing you should do is

Q = zeros(1,n);