🚀 go-pugleaf

In article <CLIFFC.92Nov15184340@miranda.rice.edu>, cliffc@rice.edu (Cliff Click) writes:
|> bbs.dennis@tsoft.sf-bay.org (Dennis Yelle) writes:
|> > because of the interest in Herman Rubin's optimization problems
|> > some people here might be interested in this.
|> > It is a real problem.  That is, I have a program that spends quite a 
|> > lot of time here, and I would like to change this if I could.  
|> 
|> > I first considered asking for a integer sqrt, but maybe if the context is 
|> > known a better answer can be given.  This program is normally run on a 
|> > machine with no floating point hardware so I would like to get rid of 
|> > floats entirely.
|> 
|> I sent him an integer square root code using Newton's Method.  I've done 
|> this problem before and I'm sure there are better methods out there.  Does 
|> somebody want to post/email something better than Newton's?

I don't know the details of your algorithm, but wouldn't it be
possible to avoid sqrt's, i.e. do the substitutions

  sqrt(x^2 + y^2) < sqrt (z^2+t^2)    => (x^2+y^2) < (z^2+y^2)
  sqrt(x^2 + y^2) < d                 => (x^2+y^2) < d^2

and so on? This demands larger integers, but that might be needed
anyway for temporary calculations?

- Olaf René 
 
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Olaf René Birkeland                 e-mail: renebi@idt.unit.no
The Norwegian Institute of Technology, University of Trondheim
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