Undefined function or variable in Matlab app designer

[poster]

I have a .m file in matlab which run perfectly. Inside I ask the user to define the path of a file uigetdir(), then I compute some .txt file with an algorithm. Then, I write the result inside a csv file.

Now, I have implemented this code inside App Designer to make a standalone application. Everything works perfectly exept that I got Undefined function or variable.

Here is a part of the code :

        Force_max=mean(F_Max_i);

        Force_max_txt=string(Force_max);

where F_Max_i is a 1x4 Matrix of double.

Those 2 lignes works correctly but later on the code I do :

Bilan_Force=["Mean";Force_max_txt];

And I got an error Undefined function or variable Force_max_txt which looks very strange to me.

Thank you

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