MATLAB System block error: The input to coder.const cannot be reduced to a constant

I'm trying to build a system block with a dynamic number of inputs. I'm able to choose the number of inputs through a dialog and it updates the number of inputs, but when I simulate the model I get: "The input to coder.const cannot be reduced to a constant".

I'm using the following code:

 function num = getNumInputsImpl(obj)
   % Define total number of inputs for system with optional 
   num = obj.NumInputs;
 end

I can't simply change it to interpreted execution, because I'm planning to use that system block to generate C code. Any thoughts?

Answer 1

[Guilherme T Silva]

Solved the problem defining the property NumInputs as nontunable.