Path: chuka.playstation.co.uk!news
From: Alex Herbert <aherbert@ndirect.co.uk>
Newsgroups: scee.yaroze.freetalk.english
Subject: Square Root
Date: Fri, 21 Aug 1998 16:24:59 +0000
Organization: PlayStation Net Yaroze (SCEE)
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OK, I know that using square roots is best avoided, and in most cases
they can be.  But sometimes they just can't be avoided.  I decided that
using floating point was not the way to go, but I've never seen a square
root algorithm before, so this is what I came up with.

u_short sq_root(u_long n) {
    u_short a=0x8000;
    u_short b=0;
    u_short c;

    while(a) {
        c=a|b;
        if(c*c<=n)
            b=c;
        a=a>>1;
    }
    return(b);
}

It works fine, but does anyone know a better way to find the sqaure root
of any u_long?


Herbs