Color input to comm.Const​ellationDi​agram object

I want to display the scatterplots of 2 different users in my simulation in real-time, for which I am using the comm.ConstellationDiagram object. I would like to use different colours for each user's scatterplot to distinguish between them. However, comm.ConstellationDiagram does not take a color input.

Scatterplot function takes a color input, but I don't want the plots on different figures each time I call it. I want the points plotted in real-time in the same figure (for each user), this is why I am using the comm.ConstellationDiagram object.

Here's a snippet of how I am using it:

constDiag1 = comm.ConstellationDiagram(2, ...
    "ChannelNames",{'Header','Data'}, ...
    "ReferenceConstellation",{refConstHeader,refConstData1}, ...
    "ShowLegend",true, ...
    "EnableMeasurements",true,...
    "Title",'User 1 constellation');

constDiag2 = comm.ConstellationDiagram(2, ...
    "ChannelNames",{'Header','Data'}, ...
    "ReferenceConstellation",{refConstHeader,refConstData2}, ...
    "ShowLegend",true, ...
    "EnableMeasurements",true,...
    "Title",'User 2 constellation');

for frame=1:framenum
    
    [rxHeader1,rxData1,rxHeader2,rxData2] = myfunction(captureData);
    
    constDiag1(complex(rxHeader1(:)), ...
                complex(rxData1(:)));
    constDiag2(complex(rxHeader2(:)), ...
                complex(rxData2(:)));
    
end

Is there a way to include a colour input to the configuration of the object?

If not, how can I go about making a custom function for obtaining scatterplots in real-time (similar to what comm.ConstellationDiagram does) where I can configure each object in a different color?

Thanks! Any help is appreciated!

Answer 1

[Walter Roberson]

You can use a single scatter() call, and record the graphics object that results. Then on subsequent loop iterations

newX = [SCATTEROBJECT.XData; real(rxHeader1(:)); real(rxData1(:)); real(rxHeader2(:)); real(rxData2(:))];
newY = [SCATTEROBJECT.YData; imag(rxHeader1(:)); imag(rxData1(:)); imag(rxHeader2(:)); imag(rxData2(:))];
newC = [SCATTEROBJECT.CData; repelem('b', numel(rxHeader1)+numel(rxData1)); repelem('r', numel(rxHeader2)+numel(rxData2))];
set(SCATTEROBJECT, 'XData', newX, 'YData', newY, 'CData', newC);

[Aswathylakshmi]

Thanks for answering! I adapted your idea for my solution.

Maybe I wasn't clear in my question: I wanted 2 different figures with scatterplots, one for each user, to compare them side-by-side. And then in each loop iteration, I wanted the figure corresponding to each user to be updated.

This is how I adapted your code:

for frame=1:framenum
    [rxData1,rxData2] = myfunction(captureData);
    if ~(exist(scatter1))
        figure
        scatter1 = scatter(real(rxData1),imag(rxData1),'b');
        title('User 1')
        drawnow
        figure
        scatter2 = scatter(real(rxData2),imag(rxData2),'r');
        title('User 2')
        drawnow
    else
        set(scatter1,'XData',real(rxData1),'YData',imag(rxData1),'CData',repmat(scatter1.CData(1,:),size(rxData1)));
        drawnow
        set(scatter2,'XData',real(rxData2),'YData',imag(rxData2),'CData',repmat(scatter2.CData(1,:),size(rxData2)));
        drawnow
    end
end

Without the drawnow, the figures are displayed only at the end of the loop, which isn't the live plotting I needed. I hope this helps the next person.

Thank you very much for the help!