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```HYPOT(3)	      DragonFly Library Functions Manual	      HYPOT(3)

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

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.

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

The cabs(), cabsf() and cabsl() functions return the absolute value of
the complex number z.

ERRORS (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; with ``reserved operand'' in place of "NaN", the same is true
on a VAX.	But programmers on machines other than a VAX (it has no infin-
ity) 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 operand 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).