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Re: Simplify needs ages to finish

  • To: mathgroup at smc.vnet.net
  • Subject: [mg44777] Re: Simplify needs ages to finish
  • From: Thomas Gutzler <gutzler at itiv.uni-karlsruhe.de>
  • Date: Thu, 27 Nov 2003 11:38:04 -0500 (EST)
  • Organization: University of Karlsruhe, Germany
  • Sender: owner-wri-mathgroup at wolfram.com

Roland Franzius wrote:
> Thomas Gutzler wrote:
> 
> 1) At least three syntax errors are in this text. Look for & & instead &&

All copy'n'paste typos..

> 2) Rewrite your SetDelayed in the following form
> o1[a1_, a2_, a3_, a4_, b1_, b2_, b3_, b4_] := 
> Evaluate[LogicalExpand[righthandside]]
> 
> This will save you some time but only if:
> 
> 3) you state the definitions in reverse order. Otherwise you are getting 
> lost alredy at definition time.

That's true but what you get is kindof strange.
I found "!!!" at least once. After that I thought: Well, if it doesn't 
simplify "!!!" to "!" it probably doesn't simplify anything. So I added 
a Simplify[..] around Evaluate[..] => took ages again :/

> 4) write a test set
> 
> test= 
> Rule@@@Transpose[{{a1,a1,...b4},Table[If[Random[]<0.5,True,False],{8}]}]
> 
> and test your definitions using values  Replace[#,test]&/@op[a1..]
> 
> 5) You need at least 256 MB memory. Otherwise disk swapping becomes time 
> consuming
> 
> 6)dont print the full result. (I have not seen it;-) Probably it will 
> take 100 times the memory used to represent the result internally.

This set of functions is only for testing purpose. I wanted to finish 
with 64 input variables and 32 output functions but I suppose I'm not 
getting a result ever :(

Thanks,
  Tom


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