Re: V8 slow like a snail

*To*: mathgroup at smc.vnet.net*Subject*: [mg127710] Re: V8 slow like a snail*From*: Bill Rowe <readnews at sbcglobal.net>*Date*: Thu, 16 Aug 2012 01:56:56 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net

On 8/15/12 at 3:33 AM, weh at snafu.de (Dr. Wolfgang Hintze) wrote: >Great disappointment on my side with 8.0.4.0 Home edition which I >installed yesterday! My first impression: looks good, many nice >features ... but incredibly slow in comparision to my good old 5.2. >I then carried out a modest benchmark test the results of which I'll >show below and which I like to express in terms of a "snail factor" >( = time in v5.2/ time in v8). Trying to compare the speed of an execution for computations from version to version in Mathematica is pretty much hopeless particularly for Integrate. It is certain Integrate has changed significantly from version 5.2 to 8. If Integrate did nothing more than a simply look for known integral solutions version 8 would have to be slower for some integrals since version 8 can solve more integrals. Look up time has to scale at least as the number of integrals tabulated. And given the need to arrange the integrand in some canonical order, my estimate here of linear with number of integrals is likely optimistic. But I am sure Integrate is far more than a look up table. Somehow the code has to decide what method to use for the integration. More capability means more code to determine what to do and more execution time. I would expect many very simple integrals such as say Integrate[x^2, {x,0,1}] to be unchanged from version 5.2 to version 8 with respect to execution time. But more complex integrals could go either way. =46inding one slower in version 8 or finding one faster in version 8 really wouldn't say much about the performance difference between version 8 and version 5.2. And ultimately, if version 5.2 works better for you then use it not version 8. For myself version 8 offers so much more than version 5.2, I cannot see using version 5.2 instead of 8 no matter how much faster version 5.2 was for some particular integral.