Multiple plots with same Legend

426 views (last 30 days)
Omar
Omar on 9 Mar 2018
Edited: Adam Danz on 29 Sep 2020
Hi colleagues, Is there a way to group different subplots with one legend. for example, I have two subplots as [subplot(1,2,1 and subplot(1,2,2)], is it possible to use the same legend for both?
Thanks in advance,

Accepted Answer

Prajith Chilummula
Prajith Chilummula on 12 Mar 2018
The issue here is that each legend needs to be associated with an axis. There is no built-in way to create an "overall legend". But it is perfectly fine to use a legend associated with a subplot as an overall legend. You will have to play with the legend's position to achieve the desired look.
The easiest way to do it is manually, by dragging the legend inside the figure.
It is a bit more involved programmatically. Here is an example:
subplot(2, 2, 1)
A = rand(10, 3);
plot(A, '-o')
hold on
b = rand(10, 1);
plot(b, '-k', 'LineWidth', 3)
subplot(2, 2, 2)
A = rand(10, 3);
plot(A, '-o')
hold on
b = rand(10, 1);
plot(b, '-k', 'LineWidth', 3)
subplot(2, 2, 3)
A = rand(10, 3);
plot(A, '-o')
hold on
b = rand(10, 1);
plot(b, '-k', 'LineWidth', 3)
subplot(2, 2, 4)
A = rand(10, 3);
plot(A, '-o', 'DisplayName', 'Data')
hold on
b = rand(10, 1);
plot(b, '-k', 'LineWidth', 4, 'DisplayName', 'Trend')
% add a bit space to the figure
fig = gcf;
fig.Position(3) = fig.Position(3) + 250;
% add legend
Lgnd = legend('show');
Lgnd.Position(1) = 0.01;
Lgnd.Position(2) = 0.4;

More Answers (1)

Adam Danz
Adam Danz on 29 Sep 2020
Edited: Adam Danz on 29 Sep 2020
Update
The graphics handles vector h in legend(h) can contain objects from any axes (created by axes(), subplot(), or tiledlayout()) from within a figure. As Prajith mentioned, the legend must be a child of a single axes but it can then be repositioned to anywhere within the figure. Starting in the r2020b release, legend positions can be changed with TiledLayout as well.
Examples:

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!