# adding legend for multiple surface in same graph

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Roni Mohammad on 21 Sep 2015
Commented: Walter Roberson on 14 Nov 2018
Hi,
I am relatively new to Matlab. I have a figure (attached) which has two surfaces . I want to create legend for each surface. Any idea/suggestion how I can create legend for each surface? I have the attached the figure.
This is my code to create this graph
close all
clear variables
clc
x=test(:,1);
y=test(:,2);
z=test(:,3);
v=test(:,4);
xlin = linspace(min(x),max(x),13);
ylin = linspace(min(y),max(y),13);
[X,Y] = meshgrid(xlin,ylin);
f = scatteredInterpolant(x,y,z);
f2 = scatteredInterpolant(x,y,v);
Z = f(X,Y);
Z2 = f2(X,Y);
figure
mesh(X,Y,Z); %interpolated
axis tight ;
hold on;
surf( X, Y, Z, 'EdgeColor', 'black', 'FaceColor', [255,100,0]/255, 'FaceAlpha', .5 );
plot3(x,y,z,'.' );
axis tight;
mesh(X,Y,Z2) %interpolated
axis tight;
surf( X, Y, Z2, 'EdgeColor', 'black', 'FaceColor', [1,255,200]/255, 'FaceAlpha', .9);
plot3(x,y,v,'.' ) %nonuniform
%hold on
xlabel('h')
ylabel('s')
zlabel('tc')
alpha(0.5) %transparent
Best,
Roni

Walter Roberson on 22 Sep 2015
Side note: you do not need surf() and then plot3(). You can use
surf( X, Y, Z, 'EdgeColor', 'black', 'FaceColor', [255,100,0]/255, 'FaceAlpha', .5, 'Marker', '.' );
To legend appropriately, you would use
h1 = surf( X, Y, Z, 'EdgeColor', 'black', 'FaceColor', [255,100,0]/255, 'FaceAlpha', .5, 'Marker', '.' );
and later
h2 = surf( X, Y, Z2, 'EdgeColor', 'black', 'FaceColor', [1,255,200]/255, 'FaceAlpha', .9, 'Marker', '.');
and then
legend([h1, h2], {'First Surface', 'Second Surface'});
Walter Roberson on 14 Nov 2018
In cases where you want aa legend that does not match the automatic legend rules, it is often easier to create some dummy invisible graphics objects that have the properties that you would like to have show up, and legend those instead . Sometimes there are ways to get the desired outputs by changing properties after calling legend but it is not clear that it is worth the fight at times .