legend dynamically updated

Hi, my task would be to have a legend which is update dynamically as I loop over some data extracted from different files and I add them to a same plot, for instance. To put it better, I would like to "append" a label to my legend every time I update my plot. Would you know how to do it?

Chiara

[John Bailey]

plot(Pss,'DisplayName','desired legend entry')

legend('-DynamicLegend')

Place that after your first plot and it will automically put the name of the plot variable into the legend.

[Walter Roberson]

Note that dynamic legends did not exist at the time the original question was asked in 2011.

[Matthew]

Those were the days.

[Moritz Stich]

Jon Bailey you are a dynamic legend. Thanks

Answer 1

[Paulo Silva]

clf
clc
hold all
x=0:0.01:2*pi;
b=zeros(5);
for a=1:5
    b(a)=plot(x,sin(a*x));
    legend(b(1:a))
    pause(1) %just to see it being draw
end

Alternative with choosen names for each plot

clf
clc
hold all
x=0:0.01:2*pi;
b=zeros(5);
c={'one','two','three','four','five'};
for a=1:5
    b(a)=plot(x,sin(a*x));
    legend(b(1:a),c(1:a))
    pause(1)
end

[Chiara Modenese]

Thanks for a very helpful community. Question is answered.

Cheers. Chiara

Answer 2

[Matt Fig]

How are you updating the plot? In a loop?

[rodolfo reyesbaez]

I added a hold on before ending the loop

Answer 3

[Chiara Modenese]

Yes, in a simple loop. Data come from different structures, but this is not so important. Basically, I want to avoid this:

legend(ss(1).name,ss(2).name,ss(3).name);

where ss(i) are structures. Every time I run my code, I can chose the number of structures to create, so I do not want to modify my legend as a function of this but, instead, do it automatically (so if I have 5 structures, I expect 5 corresponding labels in my legend, no need to modify the code by hand).

Thanks, Chiara