why i cant save files in my standalone app

Hello

when i try to save polygon.mat through my standalone app like this

save([ctfroot,'\output\polygon'],'points');

i get this error

Error using save Cannot create 'polygon.mat' because 'C:\Users\PC~1\AppData\Local\Temp\PC\mcrCache9.2\app5\output' does not exist. Error in app_new/pb_save_polygon_points (line 4131) Error in appdesigner.internal.service.AppManagementService/tryCallback (line 191) Error in matlab.apps.AppBase>@(source,event)tryCallback(appdesigner.internal.service.AppManagementService.instance(),app,callback,requiresEventData,event)

Error using matlab.ui.control.internal.controller.ComponentController/executeUserCallback (line 310) Error while evaluating Button PrivateButtonPushedFcn.

so i tried to make dir called output like this

mkdir('output')

it created the dir in the program installation folder not in this mcrCache9.2\app5\output' folder

so i want to know how to do this im really confused thanks in advance

Answer 1

[Adam]

doc mkdir

takes arguments that allow you to specify the parent folder. Never just call it with the name of the folder you want to create unless you are working in some temporary quick script and are happy for it to just create it in your working directory.

Usually, even if you do want to create it in the current directory it is good practice to include a full path.

Answer 2

[Jan]

mkdir(fullfile(ctfroot, '\output'));
save(fullfile(ctfroot, '\output\polygon'));

I would not write to the installation folder. What about using the user folder or the standard documents folder?

[Sean de Wolski]

or tempdir (guaranteed write privileges) which can then have things copied out of it as necessary.

[Ibrahim Essam]

the problem now when i create a file using this method after many seconds it's deleted and i have to save this files till the end of my program to visualize this data

[Adam]

You must have code that deletes the file in that case. Or something on your computer nothing to do with Matlab that is deleting files for you in that location.