Integer square root routine needed.
Walter Bright
bright at Data-IO.COM
Thu Aug 3 03:35:24 AEST 1989
In article <7415 at ecsvax.UUCP> utoddl at ecsvax.UUCP (Todd M. Lewis) writes:
>This may be the wrong place to post this, but I need C source
>to a reasonably fast integer square root routine.
/***************************
* Compute the square root using Newton's method.
* Donated to Public Domain.
*/
unsigned long ulsqrt(l)
unsigned long l;
{ unsigned long c1;
/* Perhaps we could do better than this for a first guess */
c1 = (l >> 1) + 1;
while (c1 * c1 > l)
{
c1 = (c1 + l / c1) >> 1;
/*printf("c1 = %ld\n",c1);*/
}
return c1;
}
If you can improve on this, please let me know.
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