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Re: Optimizing fixed point iteration

• To: mathgroup at smc.vnet.net
• Subject: [mg83100] Re: Optimizing fixed point iteration
• From: Yaroslav Bulatov <yaroslavvb at gmail.com>
• Date: Sun, 11 Nov 2007 02:54:37 -0500 (EST)
• References: <200711091017.FAA12104@smc.vnet.net><fh3rmu$13o$1@smc.vnet.net>

Sorry, only checked code with a non-fresh kernel, it should be
depth; to terminate in reasonable time, although greater depth
would give more detail

On Nov 10, 12:55 am, Murray Eisenberg <mur... at math.umass.edu> wrote:
> What value of depth are you trying to use??
>
> Yaroslav Bulatov wrote:
> > Can anyone see the trick to speed up the following code significantly?
>
> > depth;step=.02;
> > Table[(c = 0;
> >    NestWhile[-4 (# - a) (# - b) &, .51, (c++; Abs[#1 - #2] > .1) &, 2,
> >      depth]; c), {a, -1., 0., step}, {b, 0., 1., step}] // ArrayPlot
>
> > This makes a plot of the number of iterations needed for the quadratic
> > fixed point iterations to converge, as a function of quadratic
> > parameters, however it's too slow to get sufficient granularity
>
> --
> Murray Eisenberg                     mur... 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

• Follow-Ups:
  • Re: Re: Optimizing fixed point iteration
    • From: Murray Eisenberg <murray@math.umass.edu>

• References:
  • Optimizing fixed point iteration
    • From: Yaroslav Bulatov <yaroslavvb@gmail.com>