Re: Re: Mandelbrot Set & Mathematica
- To: mathgroup at smc.vnet.net
- Subject: [mg48067] Re: [mg48029] Re: Mandelbrot Set & Mathematica
- From: AGUIRRE ESTIBALEZ Julian <mtpagesj at lg.ehu.es>
- Date: Mon, 10 May 2004 06:51:23 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
On Sat, 8 May 2004, Murray Eisenberg wrote: > I don't understand the expression "=BE" in the 4th line of your code. It should be >= . Julian > > AGUIRRE ESTIBALEZ Julian wrote: > > > On Fri, 7 May 2004, fake wrote: > > > > > >>I'm looking for a program using Mathematica commands to obtain the > >>Mandelbrot set representation without using the .m file "Fractal" > >>downloadable from Mathworld. Please report the Timing parameter if you have > >>done some tests. > >>TIA > > > > > > This is what I did for a Dynamical Systems course. It is based on code > > from the help files. It includes knowledge about points that are in the > > Mandelbrot set. > > > > Clear[c, test, niter, BlackWhite, mandelbrot]; > > BlackWhite = If[# == 1, GrayLevel[0], GrayLevel[1]]&; > > niter = 100; > > test = (Abs[#] =BE 2) &; > > mandelbrot[c_] := 0 /; Abs[c] > 2; > > mandelbrot[c_] := 1 /; Abs[c + 1] < 1/4; > > mandelbrot[c_] := 1 /; 16 Abs[c]^2 < 5 - 4 Cos[Arg[c]]; > > mandelbrot[c_] := (Length@NestWhileList[(#^2+c)&,c,test,1,niter]-1)/niter; > > DensityPlot[mandelbrot[x + y I], {x, -2, .5}, {y, 0, 1}, > > PlotPoints -> {600, 300}, > > Mesh -> False, > > ImageSize -> 600, > > AspectRatio -> Automatic, > > ColorFunction -> BlackWhite]; > > > > Color can be added defining new color functions. I like > > > > rainbow = Hue[.8(1 - #)]& > > > > Julian Aguirre > > UPV/EHU > > > > > > -- > Murray Eisenberg murray at math.umass.edu > Mathematics & Statistics Dept. > Lederle Graduate Research Tower phone 413 549-1020 (H) > University of Massachusetts 413 545-2859 (W) > 710 North Pleasant Street fax 413 545-1801 > Amherst, MA 01003-9305 > > Julian Aguirre | Voice: +34 946012659 Departamento de Matematicas | Fax: +34 944648500 Universidad del Pais Vasco | Postal: Aptdo. 644, 48080 Bilbao, Spain | email: mtpagesj at lg.ehu.es