/* @(#)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 <>, <>---distance from origin INDEX hypot INDEX hypotf ANSI_SYNOPSIS #include 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 <> calculates the Euclidean distance @tex $\sqrt{x^2+y^2}$ @end tex @ifnottex <*<[x]> + <[y]>*<[y]>)>> @end ifnottex between the origin (0,0) and a point represented by the Cartesian coordinates (<[x]>,<[y]>). <> differs only in the type of its arguments and result. RETURNS Normally, the distance value is returned. On overflow, <> returns <> and sets <> to <>. You can change the error treatment with <>. PORTABILITY <> and <> are not ANSI C. */ /* * wrapper hypot(x,y) */ #include "fdlibm.h" #include #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) */