Debugging in application problem

Hello, I am having problems with my App while Debugging. In Figure-1, data and places seem to be empty, but this is not the case when I remove the breakpoint because it works well, so I had inserted a different breakpoint in an another function and I saw that everything is as it should be.(Figure-2). I can keep working on, but I think that I should post this.(I am very new to programming and Matlab, sorry for any mistakes in this post)

 function StartupFcn(app)
            load covid_data.mat covid_data
            countries = string(unique(covid_data(2:end,1)));
            M = splitapply(@(x) {x}, covid_data(2:end,2:end).', findgroups(covid_data(2:end,1).'));
            app.Global = Object_constructor("Global");
            app.Global.data = cell2mat(covid_data(2:end, 3:end));
            app.Dates = string(covid_data(1,3:end));
            app.Global.places = Object_constructor(countries);
            for ii=1:numel(countries)
                country_data = M{ii};
                app.Global.places(ii).data = cell2mat(country_data(2:end,1));
                app.Global.places(ii).data(1,3)= app.Global.places(ii).data(1,1);
                app.Global.places(ii).data(1,4)= app.Global.places(ii).data(1,2);
                for pp=1:size(country_data(2:end,1),1)-1
                    temp=app.Global.places(ii).data(pp+1,1)-app.Global.places(ii).data(pp,1);
                    temp2=app.Global.places(ii).data(pp+1,2)-app.Global.places(ii).data(pp,2);
                    if temp > 0
                        app.Global.places(ii).data(pp+1,3)= temp;
                    else
                        app.Global.places(ii).data(pp+1,3)=0;
                    end
                    if temp2 > 0
                        app.Global.places(ii).data(pp+1,4)= temp2;
                    else
                        app.Global.places(ii).data(pp+1,4)=0;
                    end
                end
                app.Global.places(ii).places = Object_constructor(string(country_data(1,2:end)));
                for jj=1:size(country_data(1,2:end),2)
                    state_data = country_data(2:end, jj+1);
                    app.Global.places(ii).places(jj).data = cell2mat(state_data);
                    if isempty(app.Global.places(ii).places(1).name)
                        app.Global.places(ii).places(jj).data(1,3) = app.Global.places(ii).places(jj).data(1,1);
                        app.Global.places(ii).places(jj).data(1,4) = app.Global.places(ii).places(jj).data(1,2);
                        for pp=1:size(country_data(2:end,1),1)-1
                            temp = app.Global.places(ii).places(jj).data(pp+1,1) - app.Global.places(ii).places(jj).data(pp,1);
                            temp2 = app.Globa.places(ii).places(jj).data(pp+1,2) - app.Global.places(ii).places(jj).data(pp,2);
                            if temp > 0
                                app.Global.places(ii).places(jj).data(pp+1,3)= temp;
                            else
                                app.Global.places(ii).places(jj).data(pp+1,3)=0;
                            end
                            if temp2 > 0
                                app.Global.places(ii).places(jj).data(pp+1,4)= temp2;
                            else
                                app.Global.places(ii).places(jj).data(pp+1,4)=0;
                            end
                        end
                    end
                end
                app.HoleCases = sum(app.Global.data(:,1:2:end-1));% I insert breakpoint here and I cannot see the places and data as can be seen in the Figure-1
                app.HoleDeaths = sum(app.Global.data(:,2:2:end));
                app.CountryListBox.Items = ["Global",app.Global.places.name];
                app.StateorRegionListBox.Items = "All";
                app.AveragedofdaysSlider.Value = 1;
                app.DailyData();
                app.Country = 0;
                app.CasesButton.Value = 1;
                app.PlotCases();
            end
 end

[Ameer Hamza]

It depends on where you add the breakpoint. For example, these values are assigned in this for loop

for ii=1:numel(countries)

If you add a breakpoint before these values are assigned, you will get empty vectors.

[Berkay Yaldiz]

Yes, I added the breakpoint at the end of this for loop

for ii=1:numel(countries)

Moreover, when I comment these lines:

                    if isempty(app.Global.places(ii).places(1).name)
                        app.Global.places(ii).places(jj).data(1,3) = app.Global.places(ii).places(jj).data(1,1);
                        app.Global.places(ii).places(jj).data(1,4) = app.Global.places(ii).places(jj).data(1,2);
                        for pp=1:size(country_data(2:end,1),1)-1
                            temp = app.Global.places(ii).places(jj).data(pp+1,1) - app.Global.places(ii).places(jj).data(pp,1);
                            temp2 = app.Globa.places(ii).places(jj).data(pp+1,2) - app.Global.places(ii).places(jj).data(pp,2);
                            if temp > 0
                                app.Global.places(ii).places(jj).data(pp+1,3)= temp;
                            else
                                app.Global.places(ii).places(jj).data(pp+1,3)=0;
                            end
                            if temp2 > 0
                                app.Global.places(ii).places(jj).data(pp+1,4)= temp2;
                            else
                                app.Global.places(ii).places(jj).data(pp+1,4)=0;
                            end
                        end
                    end

Those vectors are not empty anymore. Basically, I cannot insert a breakpoint in the startup function.

Answer 1

[Gaurav Garg]

Hey Berkay,

This seems to be the expected behvaiour of the debugger.

For the case in figure 1, I hope that the values in the variables places and data get the values assigned after you press 'Continue' on debugger.

[Berkay Yaldiz]

Thank you :)