MATLAB: “Function definitions are not permitted in this context.”

contextDefinitionserrorfunctionpermitted

I'm getting this error, but I'm not sure why. I'm using 2016a. I've attached my code file.

Best Answer

In 2016a and earlier versions (I believe this changed in R2017a), you could not define functions (except anonymous functions) in a script.

The easiest solution is to create ABD.m as a function with no arguements or outputs, so:

function ABD 
%%--------------- MAIN PROGRAM ---------------
      ... REST OF YOUR CURRENT CODE ...
end

Be sure to remember to add the final end call.

Nothing else about ‘ABD’ needs to change, except that as a function, its workspace is entirely contained within it, and will not appear in the Workspace Browser. That’s a small disadvantage, but one you can work around by simply displaying the variables you want to the Command Window. You can still call it from the Command Line as well as execute it from the Editor, since it requires no arguments.

Related Solutions

MATLAB: About functions and arguments

First before getting into the problems in the code itself, you have created a new variable SUM that aliases the builtin Matlab function of the same name. While you've done this in the function Fitt() so it will go out of scope when the function exits and not have a global alias of the name, if you were to use the sum() function internal to that program you would get unexpected results. It's good practice to avoid in general regardless of scope.

function mysum =Fitt(x)
inp =QECsimull(net1,net2,t1s,t2s,x);
...
mysum=T;
...

OK, on to your problem -- Matlab variables are in scope in the workspace or in functions unless GLOBAL (or nested functions which aren't present here). So, while you've not given enough code to tell for certain, it's likely the variables net1 net2 t1s t2s are local variables in a calling function or the workspace and so are not visible within the function Fitt().

To fix this you would have to(+) add them to the argument list in the function definition and then pass them in the call.

(+) While it is possible to make them GLOBAL this is poor practice for code maintainability and reliability so is strongly discouraged as a practice in almost all cases.

MATLAB: Having neural networks as arguments

A function has access to external functions only through the parameter list or if they are declared global. In spite of your predilections, use the former.

Hope this helps.

Thank you for formally accepting my answer

Greg

Best Answer

Related Solutions

MATLAB: About functions and arguments

MATLAB: Having neural networks as arguments

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