Unrecognized function or variable 'max'.
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I am facing an issue while using Matlab app designer.
It seems that when I am using App designer, it is giving the following error "unrecognised function or variable ''max"' for 'max'.
but when I use it in workspace without opening the app. It works fine. I have attached 2 screenshots for reference, one with app paused in debugger, other without opening the app.
And these lines of codes were working fine before, started giving problems from last 2 days.
I am not generating any variable named max within the app.
I tried both MATLAB 2021b and 2022b, same problem persists
What kind of problem this is?
Have a nice day ahead.
Walter Roberson on 27 Sep 2022
Edited: Walter Roberson on 27 Sep 2022
Somewhere in that function, or in a function that the function is nested within, you assigned to a variable named "max". In doing so, you signalled to MATLAB that everywhere within scope, that max is to be treated as a variable. Even if you later cleared max so that whos does not see it and which shows you the MATLAB function, the fact that the name existed as a variable prevents max from being used as a function name within the same scope.
It is not permitted for the same name to refer to both a variable and a function. If the first reference to max within a scope is using it as a function then you will get an error if you try to assign to max as a variable; if the first reference to max within a scope is using it as a variable then you get exactly this kind of odd error where it mysteriously cannot be used as a function even after the variable is cleared.
When you leave the scope that this occurs in, the restriction no longer holds and max suddenly starts working as a function again.
Moral of the story: using max or sum as the name of a variable are especially likely to get you into trouble, confusion over whether the name is a function or a variable.