mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-28 21:49:33 +00:00
110 lines
2.3 KiB
C
110 lines
2.3 KiB
C
|
|
||
|
|
/* @(#)w_hypot.c 5.1 93/09/24 */
|
||
|
|
/*
|
||
|
|
* ====================================================
|
||
|
|
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
|
||
|
|
*
|
||
|
|
* Developed at SunPro, a Sun Microsystems, Inc. business.
|
||
|
|
* Permission to use, copy, modify, and distribute this
|
||
|
|
* software is freely granted, provided that this notice
|
||
|
|
* is preserved.
|
||
|
|
* ====================================================
|
||
|
|
*/
|
||
|
|
|
||
|
|
/*
|
||
|
|
FUNCTION
|
||
|
|
<<hypot>>, <<hypotf>>---distance from origin
|
||
|
|
INDEX
|
||
|
|
hypot
|
||
|
|
INDEX
|
||
|
|
hypotf
|
||
|
|
|
||
|
|
ANSI_SYNOPSIS
|
||
|
|
#include <math.h>
|
||
|
|
double hypot(double <[x]>, double <[y]>);
|
||
|
|
float hypotf(float <[x]>, float <[y]>);
|
||
|
|
|
||
|
|
TRAD_SYNOPSIS
|
||
|
|
double hypot(<[x]>, <[y]>)
|
||
|
|
double <[x]>, <[y]>;
|
||
|
|
|
||
|
|
float hypotf(<[x]>, <[y]>)
|
||
|
|
float <[x]>, <[y]>;
|
||
|
|
|
||
|
|
DESCRIPTION
|
||
|
|
<<hypot>> calculates the Euclidean distance
|
||
|
|
@tex
|
||
|
|
$\sqrt{x^2+y^2}$
|
||
|
|
@end tex
|
||
|
|
@ifnottex
|
||
|
|
<<sqrt(<[x]>*<[x]> + <[y]>*<[y]>)>>
|
||
|
|
@end ifnottex
|
||
|
|
between the origin (0,0) and a point represented by the
|
||
|
|
Cartesian coordinates (<[x]>,<[y]>). <<hypotf>> differs only
|
||
|
|
in the type of its arguments and result.
|
||
|
|
|
||
|
|
RETURNS
|
||
|
|
Normally, the distance value is returned. On overflow,
|
||
|
|
<<hypot>> returns <<HUGE_VAL>> and sets <<errno>> to
|
||
|
|
<<ERANGE>>.
|
||
|
|
|
||
|
|
You can change the error treatment with <<matherr>>.
|
||
|
|
|
||
|
|
PORTABILITY
|
||
|
|
<<hypot>> and <<hypotf>> are not ANSI C. */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* wrapper hypot(x,y)
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "fdlibm.h"
|
||
|
|
#include <errno.h>
|
||
|
|
|
||
|
|
#ifndef _DOUBLE_IS_32BITS
|
||
|
|
|
||
|
|
#ifdef __STDC__
|
||
|
|
double hypot(double x, double y)/* wrapper hypot */
|
||
|
|
#else
|
||
|
|
double hypot(x,y) /* wrapper hypot */
|
||
|
|
double x,y;
|
||
|
|
#endif
|
||
|
|
{
|
||
|
|
#ifdef _IEEE_LIBM
|
||
|
|
return __ieee754_hypot(x,y);
|
||
|
|
#else
|
||
|
|
double z;
|
||
|
|
struct exception exc;
|
||
|
|
z = __ieee754_hypot(x,y);
|
||
|
|
if(_LIB_VERSION == _IEEE_) return z;
|
||
|
|
if((!finite(z))&&finite(x)&&finite(y)) {
|
||
|
|
/* hypot(finite,finite) overflow */
|
||
|
|
#ifndef HUGE_VAL
|
||
|
|
#define HUGE_VAL inf
|
||
|
|
double inf = 0.0;
|
||
|
|
|
||
|
|
SET_HIGH_WORD(inf,0x7ff00000); /* set inf to infinite */
|
||
|
|
#endif
|
||
|
|
exc.type = OVERFLOW;
|
||
|
|
exc.name = "hypot";
|
||
|
|
exc.err = 0;
|
||
|
|
exc.arg1 = x;
|
||
|
|
exc.arg2 = y;
|
||
|
|
if (_LIB_VERSION == _SVID_)
|
||
|
|
exc.retval = HUGE;
|
||
|
|
else
|
||
|
|
exc.retval = HUGE_VAL;
|
||
|
|
if (_LIB_VERSION == _POSIX_)
|
||
|
|
errno = ERANGE;
|
||
|
|
else if (!matherr(&exc)) {
|
||
|
|
errno = ERANGE;
|
||
|
|
}
|
||
|
|
if (exc.err != 0)
|
||
|
|
errno = exc.err;
|
||
|
|
return exc.retval;
|
||
|
|
} else
|
||
|
|
return z;
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* defined(_DOUBLE_IS_32BITS) */
|