Simulink Matlab Function Block

Hello,

I am trying to simulate a model using parsim. I would like to simulate the model with multiple function handles.

Since I could not pass the function handles directly to any block, I tried to utilize a Matlab function block.

This is the code in Matlab command:

model = 'model_name';
load_system(model)
in(1) = Simulink.SimulationInput(model);
in(2) = Simulink.SimulationInput(model);
C{1}= 'u(1)+2'; C{2} = 'u(1)+5'; % The two expressions are placed in a cell array
in(1) = in(1).setVariable('qq',1);
in(2) = in(2).setVariable('qq',2);
out = parsim(in, 'ShowProgress', 'on', 'TransferBaseWorkspaceVariables', 'on')

Then in the Simulink model, I use the Matlab function block with:

function y  = fcn(u,qq) % qq is taken from a constant block
coder.extrinsic('evalin','strcat')
y=0;
C = evalin('base','C{qq}');
C =strcat('@(u)',C);
C = str2func(C);
y = C(u);

This works without any error, but gives 2 identical outputs, although the elements of C are different. Specifically, the line

C = evalin('base','C{qq}');

is evaluating only the first element of the cell array C regardless of the value of qq. So both simulations in the parsim are performing u(1)+2.

Note: the model runs fine when setting q=1 or q=2 in the command window then running the Simulink model manually. The problem only appears when running the model from the command window.

Thank you