# rotnum.ode
# code to compute rotation number
# This is set up for XPP
# you can run it with a GUI or just to do the computation
# xpp rotnum.ode -silent
# plot the resulting output.dat file to see the devils staircase!
# with the GUI,
# click on InitConds Range Okay
#  
prc(x)=-.75*sin(x)
f(x,tau)=x+prc(x)+tau
x'=f(x,tau)
tau'=tau
@ bound=10000000
aux rho=x/(2*pi*max(t,1))
@ meth=discrete,total=2000,trans=1999
@ rangeover=tau
@ rangereset=no
@ rangestep=200
@ rangehigh=10,rangelow=0
@ xp=tau,yp=rho
@ xlo=0,xhi=10
@ ylo=0,yhi=1.75
@ range=1
only tau,rho
done