Plot 4 diagrams in one plot

Hi, I want to plot 4 diagrams in one plot. Actual i have two plots with 4 different values:

clear ;clc
mu=[0 0.1 1 10];
tspan=[0 20*pi];
x0=0.5;dx0=0;
IC=[x0 dx0]; % initial conditions
for i=1:4
dxdt=@(t,x)[x(2);
mu(i)*(1-x(1)^2)*x(2)-x(1)];
[T,X]=ode45(dxdt,tspan,IC);
figure(1)
plot(T,X(:,1))
hold on
xlabel('t')
ylabel('x(t)')
figure(2)
plot(X(:,1),X(:,2))
hold on
xlabel('x(t)')
ylabel('v(t)')
end
figure(1)
legend('mu=0','mu=0.1','mu=1','mu=10')
figure(2)
legend('mu=0','mu=0.1','mu=1','mu=10')

I want 4 diagrams for each value in one window (like on the right side of my picture). I have tried to input this code: But this doesn't work very good:

    ax1 = subplot(2,2,i);
    hold on 
    grid on
    box on

It should look something like this:

Answer 1

[Alan Stevens]

Like this?

mu=[0 0.1 1 10];
tspan=[0 20*pi];
x0=0.5;dx0=0;
IC=[x0 dx0]; % initial conditions
for i=1:4
dxdt=@(t,x)[x(2);
       mu(i)*(1-x(1)^2)*x(2)-x(1)];
[T,X]=ode45(dxdt,tspan,IC);
if i==1 || i==3
    subplot(2,2,i)
    plot(T,X(:,1))
    xlabel('t')
    ylabel('x(t)')
else
    subplot(2,2,i)
    plot(X(:,1),X(:,2))
    xlabel('x(t)')
    ylabel('v(t)')
end
end

[Alan Stevens]

Or like this?

mu=[0 0.1 1 10];
tspan=[0 20*pi];
x0=0.5;dx0=0;
IC=[x0 dx0]; % initial conditions
for i=1:4
dxdt=@(t,x)[x(2);
       mu(i)*(1-x(1)^2)*x(2)-x(1)];
[T,X]=ode45(dxdt,tspan,IC);
if i==1 
    subplot(2,2,i)
    plot(T,X(:,1))
    xlabel('t')
    ylabel('x(t)')
elseif i~=3
    subplot(2,2,i)
    plot(X(:,1),X(:,2))
    xlabel('x(t)')
    ylabel('v(t)')
    
end
end

[Mark S]

Hey, thanks for your fast reply. Yes it looks good. But there are some diagrams missing. I have tried to put this diagram in a picture (how i would like to have). Each function x(t) and v(t) should be on a separate window. And how can I label the axes of each diagram correctly? (in this case)

[Alan Stevens]

The following generates all the x vs t values. You could repeat for the v vs t or v vs x etc.

mu=[0 0.1 1 10];
tspan=[0 20*pi];
x0=0.5;dx0=0;
IC=[x0 dx0]; % initial conditions
for i=1:4
dxdt=@(t,x)[x(2);
       mu(i)*(1-x(1)^2)*x(2)-x(1)];
[T,X]=ode45(dxdt,tspan,IC);
if i==1 || i==2
    subplot(2,2,i)
    plot(T,X(:,1))
    xlabel('t')
    ylabel('x(t)')
elseif i ==3
    subplot(2,2,3)
    plot(T,X(:,1))
    xlabel('t')
    ylabel('x(t)')
else 
    subplot(2,2,4)
    plot(T,X(:,1))
    xlabel('t'),ylabel('x(t)')
end
end

[Alan Stevens]

Or, (finally!):

mu=[0 0.1 1 10];
tspan=[0 20*pi];
x0=0.5;dx0=0;
IC=[x0 dx0]; % initial conditions

for i=1:4
dxdt=@(t,x)[x(2);
       mu(i)*(1-x(1)^2)*x(2)-x(1)];
[T,X]=ode45(dxdt,tspan,IC);
    
    if i==1 || i==2
        figure(1)
        subplot(2,2,i)
        plot(T,X(:,1))
        xlabel('t')
        ylabel('x(t)')
        figure(2)
        subplot(2,2,i)
        plot(T,X(:,2))
        xlabel('t')
        ylabel('v(t)')
        
    elseif i ==3
        figure(1)
        subplot(2,2,i)
        plot(T,X(:,1))
        xlabel('t')
        ylabel('x(t)')
        figure(2)
        subplot(2,2,i)
        plot(T,X(:,2))
        xlabel('t')
        ylabel('v(t)')

    else 
        figure(1)
        subplot(2,2,4)
        plot(T,X(:,1))
        xlabel('t'),ylabel('x(t)')
        figure(2)
        subplot(2,2,4)
        plot(T,X(:,2))
        xlabel('t'),ylabel('v(t)')

    end
end

[Mark S]

Many thanks for your help, now it looks very good. You are my hero :)