Can't get the legend right

Hi

I plotted a few things on the chromaticity diagram below.

h1 to h3 are to plot three black lines, h4 is to plot dataset A, and h5 is to plot dataset B (with psudo code given below).

h1 = plot(line1)
h2 = plot(line2)
h3 = plot(line3)
h4 = plot(dataset A)
h5 = plot(dataset B)

When I put

legend

It shows the legend as below.

But I only need the legend for datasets A and B.

How to use the legend properly in this case?

Answer 1

[Voss]

One way is to pass the graphics objects (i.e., lines, etc.) in as inputs to legend:

figure()
h1 = plot(1:10);
hold on
h2 = plot(2:11);
h3 = plot(3:12);

% legend for h2 and h3 only
legend([h2 h3],{'h2' 'h3'})

Another way would be to set the HandleVisibility of the objects you don't want in the lengend to 'off':

figure()
h1 = plot(1:10,'HandleVisibility','off');
hold on
h2 = plot(2:11);
h3 = plot(3:12);

% no need to supply [h2 h3] as the first argument this time
% (probably still a good idea though)
legend({'h2' 'h3'})

[Salad Box]

Thank you. That really helped.

In your first method I can modify the line

legend([h2 h3],{'h2' 'h3'}) 

to

legend([h2 h3],{'A' 'B'}) 

to however I want to name the dataset.

I am not sure how I can achieve that in your second method.

[Voss]

It's the same. Let me write down the same code as in my answer, but using the names 'A' and 'B':

% Method 1
figure()
h1 = plot(1:10);
hold on
h2 = plot(2:11);
h3 = plot(3:12);

% legend for h2 and h3 only
legend([h2 h3],{'A' 'B'})

% Method 2
figure()
h1 = plot(1:10,'HandleVisibility','off');
hold on
h2 = plot(2:11);
h3 = plot(3:12);

% no need to supply [h2 h3] as the first argument this time
% (probably still a good idea though)
legend({'A' 'B'})

You really only need to use one of the above two methods, of course, and if it were up to me, I would use Method 1.

[Salad Box]

That's really useful to know. Thank you.

[Voss]

You're welcome!