glibc/sysdeps/ieee754/ldbl-96/x2y2m1.c

40 lines
1.2 KiB
C

/* Compute x^2 + y^2 - 1, without large cancellation error.
Copyright (C) 2012-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C 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 GNU C 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 GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <math.h>
#include <math_private.h>
#include <float.h>
#if FLT_EVAL_METHOD == 0
# include <sysdeps/ieee754/dbl-64/x2y2m1.c>
#else
/* Return X^2 + Y^2 - 1, computed without large cancellation error.
It is given that 1 > X >= Y >= epsilon / 2, and that X^2 + Y^2 >=
0.5. */
double
__x2y2m1 (double x, double y)
{
return (double) __x2y2m1l (x, y);
}
#endif