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Re: Most efficient method of simplifying

  • To: mathgroup at smc.vnet.net
  • Subject: [mg16543] Re: [mg16187] Most efficient method of simplifying
  • From: "Dale Horton" <daleh>
  • Date: Tue, 16 Mar 1999 04:00:18 -0500
  • Organization: Wolfram Research, Inc.
  • References: <7brr10$7af$1@dragonfly.wolfram.com>
  • Sender: owner-wri-mathgroup at wolfram.com

One of the main differences between Simplify and FullSimplify is the option
TimeConstraint. For Simplify, it is set by default to 300 seconds. For
FullSimplify, it is set to Infinity by default. If you want something in
between,
you should try using this option.

-Dale

Richard Gass wrote in message <7brr10$7af$1 at dragonfly.wolfram.com>...
>>Hello all:
>>
>>I realize this is not a well defined questions, but I'm working with some
>>fairly nasty ratios of functions (generally ratios of polynomials, but not
>>always).  At several points I do some substitutions and then I want to
>>simplify the result such that (1) all variables are removed (cancelled)
that
>>can be, and (2) the result simplifies to zero if appropriate.
>>
>>"Simplify" is the obvious choice, but I've had many cases where simplify
did
>>not cancel and/or find the zero solution.  So, I could use FullSimplify,
but
>>both versions can take days to run.  All I really need is to "expand", but
>>again there are cases where expand doesn't cancel and/or produce the zero
>>result.  "ExpandAll" can make even the simpliest expression exremely
>>complicated.
>>
>>So, I'm looking for any advice others may have for more efficient ways of
>>doing Simplify[ Expand[ ]].  As I said, this is not a well defined
question
>>& I suppose the ultimate answer is to use FullSimplify and buy the largest
>>computer available.
>>
>>Thanks,
>>
>>Greg
>Geg I have had very good luck on large expressions by first using Together
>and then Simplify. In addition to getting a simpler result this has cut
>computation time down from days to minutes in some cases
>
>Richard Gass
>Department of Physics
>University of Cincinnati
>Cincinnati, OH 45221
>phone- 513-556-0519
>E-Mail gass at physics.uc.edu
>
>
>
>
>




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