Multiple instances of gui when calling from external function

I have an external Matlab function that I wish to produce continuously update plots in the GUI created by app designer.

To get the external function to plot on the app GUI (named betaine.mlapp) I created the following public function in the app code space:

methods (Access = public)

function results = plotfit(app,x,y1,y2)

plot(app.UIAxes,x,y1);

hold(app.UIAxes);

plot(app.UIAxes,x,y2,'-b');

results = 0;

end

end

from the external function (*.m) (yo is the observed spectrum, yc is the calculated spectrum):

x = 1:m;

a = betaine;

z = plotfit(a,x,yo,yc);

It plots just fine, but every time it calls plotfit it generates a new instance of the app gui. It does this hundreds of times. How can I get it to continuously update the on the same gui?

[Geoff Hayes]

Dennis - what is

a = betaine;

? Are you creating a new instance of your app (named betaine?) everytime you call this external function?

[Geoff Hayes]

Dennis' answer moved here

Geoff --

That must be what is happening, but I don't know how to get around it. The plot function is in the app code space, and each time that it is called from an external function it creates a new instance of the app.

Thanks

[Geoff Hayes]

Dennis - perhaps you can re-use the a whenever you call that external function again? Or create the GUI just once - outside of your external function - and then pass this in as an input to your external function. So each time you call the external function (however you do this) you just pass in the GUI that you have already created and it is that GUI that you will call plotfit on. (You may need to post your external function or at least its signature and how you call it so that we can get a better idea of how it is used.)

Answer 1

[Dennis Bennett]

Geoff, Thanks. I think I figured it out, but I won't be able to try it out tomorrow: A chain of external functions are called from the app. One of those functions needs to access the app plot functions. I think that all I have to do is pass the app handles into the external function, and I can the call the app plot functions from the external function. Does this sound reasonable?

[Geoff Hayes]

Dennis - yes, this sounds reasonable. Good luck!