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A question about using odeint to solve Van der Pol equation

2 New Member
hi
I was wondering about the odeint function in scipy.
While I was solving the Van der pol equations, I found the function odeint
is not suitable. I know there are some differences between Runge-kutta method and RKF method, and only the RKF method can be used to solve the Van der Pol system.
But what should I do by the scipy function 'odeint'?
Thanks a lot!

The python program is given as follow,



#! /usr/bin/python
# Filename:vaderp ol.py


from scipy import *
from pylab import *
u=0.1
deriv= lambda y,t :array([y[1],y[0]-u*(y[0]**2-1)*y[1]])

start=0
end=20000
numsteps=100000
time=linspace(s tart,end,numste ps)
from scipy import integrate
y0=array([0.01,0.0])
y=integrate.ode int(deriv,y0,ti me,hmax=0.2,hmi n=0.0 01)
plot(time,y[:,0])
show()
Mar 1 '08 #1
0 1236

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