polarplot app.panel with condition in app designer

Hi everyone,

I currently need a way to do a polarplot in app designer with some conditions. I tried a normal polatplot in a panel and it worked but when I tried doing it with if statements it only showed up with one dot.

I have tested it in a script and it worked.

So only the for loop and the if statements do not work in app designer at the moment.

Does anyone know how to get around it or fix it?

would be much appreciated with any help.

I put this code under a button callback.

y1 = [1,2,3,4,5,6,7,8,9,10,14,13,12,11,1,1,1,1,1,1,1,1,1,1] %for example
            dotsize = 30;
            n = 7; %no. of turns
            theta1 = linspace(0,n*2*pi,length(y1));
            rho1 = linspace(1,2,numel(theta1));
            pax = polaraxes(app.Panel);
            

            
            for i = 1:length(y1)
                for ii = y1(i)
                    if ii < 3 % if score is below 3, colour red
                        polarplot(theta1(i),rho1(i),'r.','Markersize',dotsize);
                        hold on
                    elseif 3 <= ii && ii < 8 % if score is between 3 and 8 clour green
                        polarplot(theta1(i),rho1(i),'g.','Markersize',dotsize);
                        hold on
                    elseif 8 <= ii && ii <= 14 % if score is greater than 8, colour blue
                        polarplot(theta1(i),rho1(i),'b.','Markersize',dotsize);
                        hold on
                    end
                end
            end
            pax.ThetaDir = 'clockwise';
            pax.FontSize = 12;
            pax.ThetaZeroLocation = 'top';
            thetaticks(pax,[0 30 60 90 120 150 180 210 240 270 300 330])
            thetaticklabels(pax,{'00:00','02:00','04:00','06:00','08:00','10:00','12:00',...
                '14:00','16:00','18:00','20:00','22:00'})
            rticks(pax,[])

[Man Lok Lee]

Correction: I did have polarplot(pax,theta1(i),rho1(i),'r.','Markersize',dotsize);

I tried it and it still did't work

Answer 1

[Adam Danz]

I think the problem is that you're not specifying the axes but that doesn't explain why a blue dot appears and you should have seen the image appear on an external figure if my assumption is correct. Try this.

 polarplot(pax, theta1(i),rho1(i),'r.','Markersize',dotsize);
% add this ^^^  to all plolarplot() calls

You also need to apply the handle to the hold command and all graphics functions. The hold function only needs to be called once so I've moved it outside of the loop in the block below.

y1 = [1,2,3,4,5,6,7,8,9,10,14,13,12,11,1,1,1,1,1,1,1,1,1,1] %for example
dotsize = 30;
n = 7; %no. of turns
theta1 = linspace(0,n*2*pi,length(y1));
rho1 = linspace(1,2,numel(theta1));
pax = polaraxes(app.Panel);


hold(pax, 'on')
for i = 1:length(y1)
    for ii = y1(i)
        if ii < 3 % if score is below 3, colour red
            polarplot(pax, theta1(i),rho1(i),'r.','Markersize',dotsize);
        elseif 3 <= ii && ii < 8 % if score is between 3 and 8 clour green
            polarplot(pax, theta1(i),rho1(i),'g.','Markersize',dotsize);
        elseif 8 <= ii && ii <= 14 % if score is greater than 8, colour blue
            polarplot(pax, theta1(i),rho1(i),'b.','Markersize',dotsize);
        end
    end
end
pax.ThetaDir = 'clockwise';
pax.FontSize = 12;
pax.ThetaZeroLocation = 'top';
thetaticks(pax,[0 30 60 90 120 150 180 210 240 270 300 330])
thetaticklabels(pax,{'00:00','02:00','04:00','06:00','08:00','10:00','12:00',...
    '14:00','16:00','18:00','20:00','22:00'})
rticks(pax,[])

[Man Lok Lee]

oh yes sorry, I did have pax inside polarplot() , but that still didnt work

[Adam Danz]

It needs to be applied to hold, too. See updated answer.

[Man Lok Lee]

Thanks very much it worked!

But why the hold has to be outside the for loop and not inside?

[Adam Danz]

It doesn't have to be outside of the loop but calling it more than once is pointless. When you call hold(ax,'on') it sets the NextPlot property so the second time you call it, the propery is already set. By moving it outside of the loop, you're eliminating redundancy which results in cleaner code.

[Man Lok Lee]

Okay thanks for the advice!