Re: Mathematica 6.0 Desperation
- To: mathgroup at smc.vnet.net
- Subject: [mg83675] Re: Mathematica 6.0 Desperation
- From: Szabolcs Horvát <szhorvat at gmail.com>
- Date: Wed, 28 Nov 2007 05:28:59 -0500 (EST)
- References: <figtq9$fa7$1@smc.vnet.net>
Jesus M. Goiri wrote: > Dear Sirs > > I have tried some items that seem to hang Mathematica 6.0. However > they work perfectly fine in the 5.2 version. I have tried to > discover the flaw and I have not been able to do so. The problem > pertains at some code I extracted from a book about Mathematica > applications by Boccara, particularly the examples that relate to > fractals, Julia and Mandelbrot Sets. > > I have below the lines of code. I you try them, I'd wish to see if > you are able to make them work. > > Yours sincerely, > > Jesus M, Goiri > > Clear[JuliaTest] > JuliaTest = Compile[{x, y, {n, _Integer}, {c, _Complex}}, > Module[{z, num = 0}, z = x + y I; > While[Abs[z] < 2.0 && num < n, z = z^2 + c; num++]; num]] > DensityPlot[JuliaTest[x, y, 50, -0.75 + 0.5 I], > {x, 1.24, 1.27}, {y, -0.13, -0.1}, PlotPoints -> 500, > Mesh -> False, ColorFunction -> Hue] > Don't use PlotPoints -> 500 with Mathematica 6. In Mathematica 6, DensityPlot automatically increases the number of points when necessary, just like Plot did in v5. I think that it also uses interpolation to make the plot look smoother. So it is ideal for plotting smooth functions, but not so good for plotting a Julia set. ArrayPlot is a better choice here: ArrayPlot[ Table[JuliaTest[x, y, 50, -0.75 + 0.5 I], {x, 1.24, 1.27, .0001}, {y, -0.13, -0.1, .0001}], ColorFunction -> Hue] -- Szabolcs