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Why does my legend only display 50 entries?

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I have a plot with more than 50 items and I would like to add a legend for all of them. The legend gets truncated at 50.
p = plot(magic(100));
labels = cellstr(num2str((1:100)'));
legend(p,labels)
 

Accepted Answer

MathWorks Support Team
MathWorks Support Team on 20 Oct 2017
Legends are currently limited to no more than 50 entries. Usually in plots with more than 50 features, the plot is so cluttered and the legend is so large that it is more advisable to select just a few key items to display in the legend.
If you do require more than 50 entries, the workaround is to create an additional legend. This requires creating an additional hidden axes.
First plot the original data.
p = plot(magic(100));
labels = cellstr(num2str((1:100)'));
legend(p(1:50),labels(1:50),'location','westoutside')
Next create an additional axes so that the figure can have two legends. Because the new legend needs information about the color of each line, it is necessary to copy the original lines to this new axes.
set(gcf,'NextPlot','add')
newAx = axes;
newP = copyobj(p,newAx);
legend(newP(51:100),labels(51:100),'location','eastoutside')
Now make the new axes and copied lines invisible. Normally, this would be done by setting the Visible property of each line to 'off', however this would gray out the corresponding entries in the legend. Instead, set the XData and YData properties of each line to NaN.
axis(newAx,'off')
set(newP,'XData',NaN,'YData',NaN)
  1 Comment
Eric Sargent
Eric Sargent on 9 Dec 2020
Legend will cap the number of entries at 50 if no handles are specified. To have all objects in an axes show up, pass in their handles to the legend command.
p = plot(magic(100));
legend(p);

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More Answers (3)

Richard Mittleman
Richard Mittleman on 6 Sep 2019
This is an amazingly stupid way to have to do this
  6 Comments
Walter Roberson
Walter Roberson on 16 Sep 2020
You are right, I made a multiplication mistake.

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Eric Sargent
Eric Sargent on 9 Dec 2020
Legend will cap the number of entries at 50 if no handles are specified. To have all objects in an axes show up, pass in their handles to the legend command.
p = plot(magic(100));
legend(p);
  3 Comments
Dev-iL
Dev-iL on 24 Dec 2020
Thank you for pointing this out! This indicates a different problem, where the legend(target, ___) syntax has side effects that change the outcome of the funciton significantly. At the very least it's a documentation bug, but more likely a sign that the legend implementation is somewhat flawed.

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Dev-iL
Dev-iL on 24 Dec 2020
I suggest using the following undocumented feature for this:
hF = figure();
hAx = axes(hF);
plot(hAx, magic(100));
hL = legend(hAx, '-DynamicLegend');
set(hL, 'LimitMaxLegendEntries', false); % << Solution

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