# the lorenz equations # with some fancy graphics options x'=s*(-x+y) y'=r*x-y-x*z z'=-b*z+x*y par r=27,s=10,b=2.66 init x=-7.5,y=-3.6,z=30 # now add some projection planes for 2D plote aux x2=xplane aux y2=yplane aux z2=zplane par xplane=-35,yplane=60,zplane=-10 # set up the numerics @ total=50,dt=.02 # set up 3D plot @ xplot=x,yplot=y,zplot=z,axes=3d # tell XPP there are 4 plots altogether @ nplot=4 # here are the 3 projections @ xp2=x,yp2=y,zp2=z2 @ xp3=x,yp3=y2,zp3=z @ xp4=x2,yp4=y,zp4=z # set up the 3D window @ xmin=-40,xmax=18,ymin=-24,ymax=64,zmin=-12,zmax=45 @ xlo=-1.4,ylo=-1.7,xhi=1.7,yhi=1.7 # and rotate the plot a bit so it looks nice @ theta=35 done