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HYPOT(3)	       FreeBSD Library Functions Manual		      HYPOT(3)

NAME
     hypot, hypotf, hypotl, cabs, cabsf, cabsl -- Euclidean distance and com-
     plex absolute value functions

LIBRARY
     Math Library (libm, -lm)

SYNOPSIS
     #include <math.h>

     double
     hypot(double x, double y);

     float
     hypotf(float x, float y);

     long double
     hypotl(long double	x, long	double y);

     #include <complex.h>

     double
     cabs(double complex z);

     float
     cabsf(float complex z);

     long double
     cabsl(long	double complex z);

DESCRIPTION
     The hypot(), hypotf() and hypotl()	functions compute the sqrt(x*x+y*y) in
     such a way	that underflow will not	happen,	and overflow occurs only if
     the final result deserves it.  The	cabs(),	cabsf()	and cabsl() functions
     compute the complex absolute value	of z.

     hypot(infinity, v)	= hypot(v, infinity) = +infinity for all v, including
     NaN.

ERROR (due to Roundoff,	etc.)
     Below 0.97	ulps.  Consequently hypot(5.0, 12.0) = 13.0 exactly; in	gen-
     eral, hypot and cabs return an integer whenever an	integer	might be
     expected.

NOTES
     As	might be expected, hypot(v, NaN) and hypot(NaN,	v) are NaN for all
     finite v.	But programmers	might be surprised at first to discover	that
     hypot(+-infinity, NaN) = +infinity.  This is intentional; it happens
     because hypot(infinity, v)	= +infinity for	all v, finite or infinite.
     Hence hypot(infinity, v) is independent of	v.  Unlike the reserved	oper-
     and fault on a VAX, the IEEE NaN is designed to disappear when it turns
     out to be irrelevant, as it does in hypot(infinity, NaN).

SEE ALSO
     carg(3), math(3), sqrt(3)

STANDARDS
     The hypot(), hypotf(), hypotl(), cabs(), cabsf(), and cabsl() functions
     conform to	ISO/IEC	9899:1999 (``ISO C99'').

HISTORY
     Both a hypot() function and a cabs() function appeared in Version 7 AT&T
     UNIX.

FreeBSD	11.2			March 30, 2008			  FreeBSD 11.2

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | ERROR (due to Roundoff, etc.) | NOTES | SEE ALSO | STANDARDS | HISTORY

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