famous feather map
- To: mathgroup at smc.vnet.net
- Subject: [mg52296] famous feather map
- From: Roger Bagula <tftn at earthlink.net>
- Date: Sun, 21 Nov 2004 07:23:35 -0500 (EST)
- Reply-to: tftn at earthlink.net
- Sender: owner-wri-mathgroup at wolfram.com
Dr Pickover published a program for this in Algorthm
in the early 90's as well. Gumowski and Mira made up this
model as a physics experiment.
Clear[x,y,a,b,s,g,a0]
(* Mira map: from Fractals ( Endlessly Repeated Geometrical Figures)
page136 by Hans Lauwerier,1991*)
(* famous feather map*)
f[x_]:=a0*x+2*(1-a0)*x^2/(1+x^2)
a0=-.48;b0=0.93;
digits=10000;
x[n_]:=x[n]=N[b0*y[n-1]+f[x[n-1]],100]
y[n_]:=y[n]=N[-x[n-1]+f[x[n]],100]
x[0]=15;y[0]=0;
a=Table[{x[n],y[n]},{n,0, digits}];
ListPlot[a, PlotRange->All]
Respectfully, Roger L. Bagula
tftn at earthlink.net, 11759Waterhill Road, Lakeside,Ca 92040-2905,tel: 619-5610814 :
alternative email: rlbtftn at netscape.net
URL : http://home.earthlink.net/~tftn