Mismatch legend and plots

I've read a few posts about people having the same issue but i can't fix it myself.

I have different figures and I plot them and add their legends but the color doesn't match with the plots nor does the type of line. I have a marker and the legend displays it as a straight line

figure('Name','Voltaje Inducido Corriente Directa')
hold on 
plot(tiempo1(2:end),voltaje_dc_1,'r')
plot(tiempo2,voltaje_dc_2,'ob','markerfacecolor','b')

title("Voltaje Inducido")
xlabel('Tiempo') 
ylabel('Voltaje Inducido') 
legend('Voltaje Ind corriente directa tiempo 1','Voltaje Ind corriente directa tiempo 2')
hold off

Looks something like this:

my variables "voltaje_dc_1" and "voltaje_dc_2" are arrays of different lenght

voltaje_dc_1 = 299 x 299

voltaje_dc_2 = 1 x 90

Answer 1

[Walter Roberson]

When you have a 2D array of Y values, then one output line is created for each column of Y (though sometimes it is for each row instead, of that is what is needed to make it match the number of x elements.)

legend() wants to create a legend for all the lines.

figure('Name','Voltaje Inducido Corriente Directa')
hold on 
h1 = plot(tiempo1(2:end),voltaje_dc_1,'r')
h2 = plot(tiempo2,voltaje_dc_2,'ob','markerfacecolor','b')

title("Voltaje Inducido")
xlabel('Tiempo') 
ylabel('Voltaje Inducido') 
legend([h1(1), h2(1)], {'Voltaje Ind corriente directa tiempo 1','Voltaje Ind corriente directa tiempo 2'})
hold off

[Hg]

Thank you very much. It worked right away!

For what I see you defined variables "h1" and "h2" for the plots and then for the legend you assigned them the labels just to the first element of each of the arrays?

[Walter Roberson]

Yes, exactly. h1 at least will be a vector of line object handles, and you want to select one representative one of them to insert into the legend.

[Hg]

Got it! Thanks again

[Cheuk Yin Wong]

This also helps with my problem I currently have, thanks. May I ask what is the (1) in h1(1)? Thanks.

[Walter Roberson]

@Cheuk Yin Wong

When you have a 2D array of Y values, then one output line is created for each column of Y. One handle is returned for each of those lines. The (1) narrows it down to the first of the handles.

In the case of this example, h1(1) would be the handle to the line for the first column of voltaje_dc_1

[Cheuk Yin Wong]

Thank you very much!