Re: much power to mathematica

*To*: mathgroup at smc.vnet.net*Subject*: [mg125368] Re: much power to mathematica*From*: David Bailey <dave at removedbailey.co.uk>*Date*: Sat, 10 Mar 2012 06:14:50 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <jj4qn7$ifa$1@smc.vnet.net> <15040062.90100.1331201203073.JavaMail.root@m06> <jjcob0$q6e$1@smc.vnet.net>

On 09/03/2012 11:08, djmpark wrote: > David, > > There is a case where parallel processing will give a gain much greater than > the number of cores used! This is when breaking a complicated graphic, say a > contour or density plot, into multiple pieces. > > If you have to use 200 x 200 PlotPoints for a regular plot, then you can > break it into four 100 x 100 plots for the same resolution. You obtain the > approximate factor of 4 but also much faster execution because you are using > only 1/4 the PlotPoints for each plot. There might also be some improvement > with MaxRecursion, because each plot is simpler. > > I've found that the easiest way to understand and use parallel processing is > to learn about and use ParallelSubmit and WaitAll. > > David, Wouldn't that imply that the plotting process could be speeded up anyway be splitting it up into smaller pieces? Also, I imagine that the contour plot must deteriorate if constructed in this way - contours not joining across the borders, etc. I mean the parallel computation isn't computing the same result as the original sequential one. David Bailey http://www.dbaileyconsultancy.co.uk