| 0,0 → 1,111 |
|---|
| |
| /* @(#)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) |
| */ |
| |
| #define _IEEE_LIBM |
| |
| #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) */ |