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matlabdynamicmatlab-figurelegend

How to Get Dynamic Legend on Linear Graph in Loop?

Diff conditions: how to clear dynamic legends at the end of each iteration; how to remove fitted linear lines at the end of each iteration.

I am trying to extend this answer of the thread Dynamic Legend (Updates in every recursion) to iterate legend on one graph. Proposal to cover dynamic legend on one linear graph

close all; clear all; 

% Test data
aSize=zeros(2,777);
aSize=[[0, 0]' randi(3,2,777)]; % STDEV about 3

x=0:1:180; 

hFig=figure; 

index=1;
while (index<=7); 

    % origo left alone
    aSize(:, index+1) = aSize(:, index+1) + index; % to have linearly increasing trend

    sz=40; 
    legend('-DynamicLegend');
    h = scatter(aSize(1,1:index+1)', aSize(2,1:index+1)', sz, ...
          'MarkerEdgeColor',[0 .5 .5],...
          'MarkerFaceColor',[0 .7 .7],...
          'LineWidth',1.5, ...
          'DisplayName', sprintf('Data'));
    xlabel('width'); ylabel('height');
    hold on; 

    % Optimum
    x=0:1:max( aSize(1, 1:index+1) ); 
    y = x; % assume uniform
    grid on; 
    h1=plot(x,y, 'black', ...
        'DisplayName', sprintf('Optimum'));

    % Fit with R2 linear
    x=aSize(1,1:index+1); 
    b1 = aSize(1,1:index+1)' \ aSize(2,1:index+1)'; 
    yCalc1 = b1 * aSize(1,1:index+1);
    Rsq1 = 1 - sum((y(1:index+1) - yCalc1).^2)/sum((y(1:index+1) - mean(y(1:index+1))).^2)

    % origo needed
    x = [0 x]; 
    yCalc1 = [0 yCalc1]; 
    h2=plot(x(1:index+2)', yCalc1(1:index+2)', '--p', ...
        'DisplayName', sprintf('Fit R2 = %d', Rsq1)); 

    drawnow; 

    index=index+1;

end;

Output unsuccessful where legends are just appended

enter image description here

MATLAB: 2016a
OS: Debian 8.5 6 bit
Linux kernel: 4.6 of backports
Hardware: Asus Zenbook UX303UA

Solution

  • Remove this line legend('-DynamicLegend'); and write it just before the drawnow line and write hold off after that line. So the following will be the lines at the end of your loop.

    legend('-DynamicLegend');
drawnow; 
hold off
index=index+1;