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Subject: Re: Log base 2
From: Jeff Waltzer (jeffwaltzer_at_yahoo.com)
Date: 2002-09-19


   This code on that link:

 g = 15;
 while(g && !(x&0x8000) ) // loop until msb of x occupies bit 15
 {
   x <<= 1;
   g--;
 }

is pretty much what I was suggesting. :)

--- Philipp Pertermann <philipp.pertermann_at_web.de> wrote:
> From: "Jeff Waltzer"
>
>
> >
> > One could do a primitive approximation of a Log base 2
> function by
> > rotating the bits to find the left most location set bit.
> This would be
> > good if all you need is a number from 0 to 15.
>
> I believe I already found the perfect link. I just hate math
> and have been to lazy to understand that yet.
> http://www.dattalo.com/technical/theory/logs.html
>
> Phil
>

=====
Whoever fights monsters should see to it that in the process he doesn't become a monster.
--Frederick Wilhelm Nietsche

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