Can't start Classification Learner

With Matlab 2019b I am not able to start Classification learner. It is installed in a huge system, constrained with Win 7.

Just starting Matlab and click on the learner app, I get:

Warning: The following error was caught while executing 'mlearnapp.internal.MLearnApp' class destructor:

Dot indexing is not supported for variables of this type.

Error in mlearnapp.internal.MLearnApp/delete (line 120)

this.MainToolstripView.delete();

Error in mlearnapp.internal.MLearnApp (line 78)

this.Session = session;

Error in mlearnapp.internal.ui.DialogFactory/createMLearnAppWindow (line 32)

window = mlearnapp.internal.MLearnApp(session, newSessionCreator, dialogFactory, toolGroup, problemDependentToolstripFactory,

mainThreadBusyTracker);

Error in classificationLearner (line 28)

h = dialogFactory.createMLearnAppWindow(session, newSessionCreatorFactory, groupTag, appTitleMessage, problemDependentToolstripFactory,

mainThreadBusyTracker);

> In mlearnapp.internal.MLearnApp (line 78)

In mlearnapp.internal.ui/DialogFactory/createMLearnAppWindow (line 32)

In classificationLearner (line 28)

Error using strjoin (line 14)

Expected input to be one of these types:

char

Error in mlearnapp.internal.ui.toolstrip.NewSessionSplitButtonView>iAddLinebreaksToButtonLabel (line 92)

outstring = strjoin(splittedString, '\n');

Error in mlearnapp.internal.ui.toolstrip.NewSessionSplitButtonView>iCreateSplitButton (line 75)

string = iAddLinebreaksToButtonLabel(iMessageString(messageID));

Error in mlearnapp.internal.ui.toolstrip.NewSessionSplitButtonView (line 45)

this.Button = iCreateSplitButton(icon, ...

Error in mlearnapp.internal.ui.toolstrip.ToolstripFactory/createNewSessionButtonPresenter (line 15)

view = mlearnapp.internal.ui.toolstrip.NewSessionSplitButtonView();

Error in mlearnapp.internal.ui.DialogFactory/createMainToolstripPresenter (line 48)

newSessionButtonPresenter = toolstripFactory.createNewSessionButtonPresenter(this.MATLABOnlineChecker, session, newSessionCreator,

mainThreadBusyTracker);

Error in mlearnapp.internal.MLearnApp (line 91)

this.MainToolstripPresenter = this.DialogFactory.createMainToolstripPresenter( ...

Error in mlearnapp.internal.ui.DialogFactory/createMLearnAppWindow (line 32)

window = mlearnapp.internal.MLearnApp(session, newSessionCreator, dialogFactory, toolGroup, problemDependentToolstripFactory,

mainThreadBusyTracker);

Error in classificationLearner (line 28)

h = dialogFactory.createMLearnAppWindow(session, newSessionCreatorFactory, groupTag, appTitleMessage, problemDependentToolstripFactory,

mainThreadBusyTracker);

Can you give me any hint on where to strt looking?

Best regards

Pål G. Larsson M.D., PhD.

Head of Clinical Neurophysiology

Department of Neurosurgery

Division of Surgery and Clinical Neuroscience

Oslo University Hospital

Answer 1

[Hritika Suneja]

The error seems to be occuring because of a file missing in the search path. Restoring MATLAB search path to its default state may help resolve the issue.

Before modifying the search path, it is important to make a backup of 'pathdef.m' file, by copying it to another folder whoch is not on the search path. The pathdef.m file can be located with the help of the following command:

>> which -all pathdef 

After making the backup, MATLAB's search path can be restored to it's default state by executing the following commands in the MATLAB command window:

>> restoredefaultpath 
>> rehash toolboxcache 

If the classification learner now starts without an error , the search path can be saved by executing the following command in the MATLAB command window:

>>savepath

Hope this helps !

[Supriya Gain]

I'm getting errors while fitting the classification model. Can you tell me how to solve that?

Answer 2

[Bahaa Musawi]

Excellent! works