Re: How I can I optimize the following code in order to get very

*To*: mathgroup at smc.vnet.net*Subject*: [mg125108] Re: How I can I optimize the following code in order to get very*From*: Szabolcs <szhorvat at gmail.com>*Date*: Wed, 22 Feb 2012 05:28:43 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <jhvu3d$7vc$1@smc.vnet.net>

On Tuesday, 21 February 2012 13:10:37 UTC+2, Liwen Zhang wrote: > How I can I optimize the following code in order to get very short > running time? > > Time1 = AbsoluteTime[]; > n = 3000; > Do[Do[x = > Sin (45.0)*ArcSin (0.5)*Sqrt (5.0)*ArcTan (2.5555);, {n}], {n}]; > Time2 = AbsoluteTime[]; > Print[Time2 - Time1]; This program does not do anything except calculate the same thing n*n times. Since you have no varying parameters in the expression, you can just calculate the value once. Generally, a good and easy way to speed up programs is compiling them: http://reference.wolfram.com/mathematica/ref/Compile.html Here's a detailed list of tips and guidelines on how to use Compile effectively, by Leonid Shifrin: http://mathematica.stackexchange.com/a/1816/12 Here's another post on general performance tuning in Mathematica, also written by Leonid Shifrin: http://stackoverflow.com/a/4723969/695132 Here's a more advanced tutorial on using Compile[], from the docs: http://reference.wolfram.com/mathematica/Compile/tutorial/Overview.html Finally, you'll find a collection of link to performance tuning tutorials / presentations here: http://mathematica.stackexchange.com/tags/performance-tuning/info as well as several discussions on performance tuning here: http://mathematica.stackexchange.com/questions/tagged/performance-tuning