Legend for multiple plots varying parameters

Pleas, how do I make my legend to match with my data? I have attached the figure. I want the legend data1 to corresponds to xi = -0.06, t=0, data2 to corresponds to xi=-0.05, t=0, data3: xi = -0.06, t=25, data4: xi = -0.05, t=25 and so on ..

% matlab and maple for theta plot for different xi values
figure
subplot(2,1,1)
hold on
for ixi = 1:2
    if ixi == 1
        plot(z, squeeze(THETA(ixi,it,:)), 'c', z2, thetasolxi,'r'); 
    else
        plot(z, squeeze(THETA(ixi,it,:)),'g--', z2, thetasolxi2, 'b--');
    end
    xlabel('z (\mu m)')
    ylabel('\theta(z,t)(rad)')
    title('Comparison of \theta(z,t) plot for \xi for maple and matlab' )
end 
legend('show')
% matlab and maple for v plot for different xi values
subplot(2,1,2)
hold on
for ixi = 1:2
    if ixi == 1
        plot(z, squeeze(V(ixi,it,:)), 'c', z2, vsolxi2,'r--'); 
    else
        plot(z, squeeze(V(ixi,it,:)),'g', z2, vsolxi, 'b--');
    end
    xlabel('z (\mu m)')
    ylabel('v(z,t)(m/s)')
    title('Comparison of v(z,t) plot for \xi for maple and matlab' )
end 
legend('show')

[Sharmin Kibria]

You can try

legend('xi = -0.06, t=0', 'xi=-0.05, t=0', 'xi = -0.06, t=25', 'xi = -0.05, t=25') . The number of character vectors in legend must be equal to the number of data you are plotting. Otherwise it will error out.

[University Glasgow]

Okay, thank you

Answer 1

[Walter Roberson]

% matlab and maple for theta plot for different xi values
figure
subplot(2,1,1)
hold on
for ixi = 1:2
    xi_part = "xi = " + Xis(ixi);
    t_part = ", t = " + Times(it);
    dn = xi_part + t_part;
    if ixi == 1
        plot(z, squeeze(THETA(ixi,it,:)), 'c', z2, thetasolxi,'r', 'DisplayName', dn); 
    else
        plot(z, squeeze(THETA(ixi,it,:)),'g--', z2, thetasolxi2, 'b--', 'DisplayName', dn);
    end
    xlabel('z (\mu m)')
    ylabel('\theta(z,t)(rad)')
    title('Comparison of \theta(z,t) plot for \xi for maple and matlab' )
end 
legend('show')
% matlab and maple for v plot for different xi values
subplot(2,1,2)
hold on
for ixi = 1:2
    xi_part = "xi = " + Xis(ixi);
    t_part = ", t = " + Times(it);
    dn = xi_part + t_part;

    if ixi == 1
        plot(z, squeeze(V(ixi,it,:)), 'c', z2, vsolxi2,'r--', 'DisplayName', dn); 
    else
        plot(z, squeeze(V(ixi,it,:)),'g', z2, vsolxi, 'b--', 'DisplayName', dn);
    end
    xlabel('z (\mu m)')
    ylabel('v(z,t)(m/s)')
    title('Comparison of v(z,t) plot for \xi for maple and matlab' )
end 
legend('show')

[University Glasgow]

Hi, thank you for this but i it returned this error:

Unrecognized function or variable 'Xis'.

I have attached my code

[Walter Roberson]

you have

for xi = [-0.05, -0.06]

Instead,

Xis = [-0.05, - 0.06];
for xiidx = 1:length(Xis)
  xi = Xis(xiidx);

I am unable to find a definition for "it" in your code, so I am not sure what should be used to initialize Times

[University Glasgow]

Thank you. My it = 1:round(nt/4):nt. The code it is working but the times are still the same. Find attached the figure

[Torsten]

We cannot see where and how you use this

it = 1:round(nt/4):nt

in your plotting part.

As far as I can see, "it" is never set in the code you attached.

[University Glasgow]

Thank you , after the defining the it, Is working now.