www.gusucode.com > Matlab源程序 > Matlab源程序/精通Matlab综合辅导与指南-源程序/vdpol.m
function yprime=vdpol(t,y); %VDPOL(t,y) returns the state derivatives of the Van der Pol equation: % % x'' - mu*(1-x^2)*x' + x = 0 (' = d/dx, '' = d^2/dx^2) % % let y(1) = x and y(2) = x' % % then y(1)' = y(2) % y(2)' = mu*(1-y(1)^2)*y(2) -y(1) global MU yprime=[y(2);MU*(1-y(1)^2)*y(2)-y(1)]; % output must be a column