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So for my code im trying to vary two parameters used in a system of differential equations and evaluate how those different values affect a subset of the solution. I want to do this by creating a contour plot, but I cant seem to get my data to ailgn correctly.

X= linspace(1,5,5); % Vector for alpha_p values

Y= linspace(0.5,3,5); % Vector for beta_p values

[A, B]= meshgrid(X,Y);

for i= 1:length(A)

for j=length(B)

[t,x] = ode45(@(t,x) pulsegenerator_function2(t, x, 1, 5, 0.75, A(i,j), B(i,j), 5,...

0.75, A(i,j), B(i,j), 1, 2, 0.75, A(i,j), B(i,j), 3, 1, 2, 1 ), linspace(0,10,75), [0.1 0 0 0 0 0]);

so this is what I have right now, essentially I have a bunch of paramenters (as you can see after t and x in the function) and I'm trying to vary 2 of them at all possible combnations with each other and i dont know how to successfully do that.

After this issue I still dont understand how I can get the right size data to work for making a contour plot, but it might have to do with this first part so thats the most pressing issue at the moment

KSSV
on 1 Aug 2020

X= linspace(1,5,5); % Vector for alpha_p values

Y= linspace(0.5,3,5); % Vector for beta_p values

[A, B]= meshgrid(X,Y);

nt = length(x) ; [m,n] = size(A) ;

Z = zeros(m,n,nt) ;

for i= 1:length(A)

for j=length(B)

[t,x] = ode45(@(t,x) pulsegenerator_function2(t, x, 1, 5, 0.75, A(i,j), B(i,j), 5,...

0.75, A(i,j), B(i,j), 1, 2, 0.75, A(i,j), B(i,j), 3, 1, 2, 1 ), linspace(0,10,75), [0.1 0 0 0 0 0]);

Z(i,j,:) = x ;

end

end

for i = 1:nt

contour(A,B,Z(:,:,i)

title(sprintf("contour at time step = %d",i))

drawnow

pause(1)

end

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