mirror of
https://review.haiku-os.org/buildtools
synced 2025-02-01 02:54:39 +01:00
52 lines
1.5 KiB
C
52 lines
1.5 KiB
C
|
/* __gmpfr_isqrt && __gmpfr_cuberoot -- Integer square root and cube root
|
||
|
|
|
||
|
|
Copyright 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
|
||
|
|
Contributed by the Arenaire and Cacao projects, INRIA.
|
||
|
|
|
||
|
|
This file is part of the MPFR Library.
|
||
|
|
|
||
|
|
The MPFR Library is free software; you can redistribute it and/or modify
|
||
|
|
it under the terms of the GNU Lesser General Public License as published by
|
||
|
|
the Free Software Foundation; either version 2.1 of the License, or (at your
|
||
|
|
option) any later version.
|
||
|
|
|
||
|
|
The MPFR Library is distributed in the hope that it will be useful, but
|
||
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
||
|
|
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
|
||
|
|
License for more details.
|
||
|
|
|
||
|
|
You should have received a copy of the GNU Lesser General Public License
|
||
|
|
along with the MPFR Library; see the file COPYING.LIB. If not, write to
|
||
|
|
the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
|
||
|
|
MA 02110-1301, USA. */
|
||
|
|
|
||
|
|
#include "mpfr-impl.h"
|
||
|
|
|
||
|
|
/* returns floor(sqrt(n)) */
|
||
|
|
unsigned long
|
||
|
|
__gmpfr_isqrt (unsigned long n)
|
||
|
|
{
|
||
|
|
unsigned long s;
|
||
|
|
|
||
|
|
s = 1;
|
||
|
|
do {
|
||
|
|
s = (s + n / s) / 2;
|
||
|
|
} while (!(s*s <= n && n <= s*(s+2)));
|
||
|
|
return s;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* returns floor(n^(1/3)) */
|
||
|
|
unsigned long
|
||
|
|
__gmpfr_cuberoot (unsigned long n)
|
||
|
|
{
|
||
|
|
double s, is;
|
||
|
|
|
||
|
|
s = 1.0;
|
||
|
|
do {
|
||
|
|
s = (2*s*s*s + (double) n) / (3*s*s);
|
||
|
|
is = (double) ((int) s);
|
||
|
|
} while (!(is*is*is <= (double) n && (double) n < (is+1)*(is+1)*(is+1)));
|
||
|
|
return (unsigned long) is;
|
||
|
|
}
|
||
|
|
|