MATLAB: Plot multiple subintervals in one figure

differential equationsplot

Hello all. Probably quite an easy problem but I am stuck.
f=@(t,u)-u+sin(5*t)+cos(2*t);
a=0; b=5; ua=2; % begynnelsevillkor
t=linspace(a,b,15); u=linspace(-2,2,15);
riktningsfaelt(f,t,u);
N=10; h=(b-a)/N; %steglängd
T=linspace(a,b,N+1); U=zeros(size(T)); 
U(2)=ua; %enligt begynnelsevillkor
for n=1:N
U(n+1)=U(n)+h*f(T(n),U(n)); % Eulers metod
end
plot(T,U)
So what I want to do is plot but with different N values in the same figure. I have tried "hold on" then set a new N value but it doesn't work. Lets say I want to plot N=10 and N=100 in the same figure, how do I do that??

Best Answer

Joakim, is this what you had in mind?
f=@(t,u)-u+sin(5*t)+cos(2*t);
a=0; b=5; ua=2; % begynnelsevillkor
t=linspace(a,b,15); u=linspace(-2,2,15);
% riktningsfaelt(f,t,u);
for N = 10:10:100
    h=(b-a)/N; %steglängd
    T=linspace(a,b,N+1);
    U=zeros(size(T));
    U(2)=ua; %enligt begynnelsevillkor
    for n=1:N
        U(n+1)=U(n)+h*f(T(n),U(n)); % Eulers metod
    end
    plot(T,U)
    hold on
end
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