# an example due to Geisel with 1/f spectral properties par a=1.5,b=.5 x'=u y'=v u'=(a+b*cos(y))*sin(x) v'=(a+b*cos(x))*sin(y) init x=-30,y=-50,u=1,v=.5 @ total=8000,dt=.25,maxstor=100000,bound=100000,meth=qualrk done