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Topic: Forced Van der Pol HELP
Replies: 1   Last Post: Feb 20, 2013 10:46 AM

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 sam Posts: 16 Registered: 2/20/13
Forced Van der Pol HELP
Posted: Feb 20, 2013 6:44 AM

Hi i've looked for help with this problem all over but found little to no help.

I'm simply trying to model a forced Van der Pol oscillator (ie instead of making diff equation = 0 now make it =cos(wt)). I need to update my function "vdp" 's 't' term as i run the code. I don't see how i can do this (ie i want the t term in the cos function to increment for each execution). Please any help would be greatly appreciated.

My code:
vdp file:

function dydt = vdp(t,y,Mu)
dydt =[y(2);Mu*(1-y(1)^2)*y(2)-y(1)+Mu*(sin(800*pi*t)+sin(900*pi*t))];
% End solvevdp.m

test file:
t = [1:100:1]
Mu= 1000;

ode= @(t,y) vdp(t,y,Mu);
[t,y]=ode23(ode,[0, 3000],[2;0]);

plot(t,y(:,1))
title('van der Pol Equation, \mu = 1000')
axis([0 3000 -3 3])
xlabel('t')
ylabel('solution y')

Date Subject Author
2/20/13 sam
2/20/13 sam