MathGroup Archive 2007

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: FactorInteger slow in V6.0 vs V5.2

  • To: mathgroup at smc.vnet.net
  • Subject: [mg81207] Re: FactorInteger slow in V6.0 vs V5.2
  • From: Costa Bravo <laguna at aol.com>
  • Date: Sat, 15 Sep 2007 04:17:34 -0400 (EDT)
  • References: <fcb37e$fba$1@smc.vnet.net>

Mark Fisher write:
> In version 5.2 the following runs pretty fast (not more than a couple
> of minutes)
> 
> FactorInteger[2^227-1]
> 
> but quite slow in version 6.0 (I'm not sure how long). Any ideas as to
> why?

j.f.b.payne at tesco.net wrote :
 > I get ~1200seconds on both version 5.2 and version 6 (Linux,AMD64, ~4GHz)
 > (unless you've got a 10 times faster machine than me)

sydgeraghty at mac.com wrote :
 > $Version -> "6.0 for Mac OS X x86 (32-bit) (June 19, 2007)"
 > MacBookPro2,1.   Intel Core 2 Duo, 2.33 GHz

 > Timing
 > {984.557, {{26986333437777017,
 >    1}, {7992177738205979626491506950867720953545660121688631, 1}}}

Results for my machine :

SVersion -> 5.1 Microsoft Windows  , XP
Intel Pentium 4, Speed 3.0 GHz

Timing[FactorInteger[2^227-1]

{86.782 Second  (*!!*), {{26986333437777017, 1},
{7992177738205979626491506950867720953545660121688631, 1}}}

Why such big differences are in timing ?

-- 
   Costa



  • Prev by Date: Re: FactorInteger slow in V6.0 vs V5.2
  • Next by Date: PlotMarkers misalignment in Mathematica 6.0.0
  • Previous by thread: Re: FactorInteger slow in V6.0 vs V5.2
  • Next by thread: Distinguishing Strings from Symbols