HYPOT(3)                            Linux Programmer's Manual                            HYPOT(3)



NAME
       hypot, hypotf, hypotl - Euclidean distance function

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);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       hypot():
           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE || _ISOC99_SOURCE ||
           _POSIX_C_SOURCE >= 200112L;
           or cc -std=c99
       hypotf(), hypotl():
           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE ||
           _POSIX_C_SOURCE >= 200112L;
           or cc -std=c99

DESCRIPTION
       The  hypot()  function  returns  sqrt(x*x+y*y).  This is the length of the hypotenuse of a
       right-angled triangle with sides of length x and y, or the distance  of  the  point  (x,y)
       from the origin.

       The  calculation  is performed without undue overflow or underflow during the intermediate
       steps of the calculation.

RETURN VALUE
       On success, these functions return the length of a right-angled  triangle  with  sides  of
       length x and y.

       If x or y is an infinity, positive infinity is returned.

       If x or y is a NaN, and the other argument is not an infinity, a NaN is returned.

       If  the  result  overflows,  a  range  error  occurs,  and  the functions return HUGE_VAL,
       HUGE_VALF, or HUGE_VALL, respectively.

       If both arguments are subnormal, and the result is subnormal, a range  error  occurs,  and
       the correct result is returned.

ERRORS
       See  math_error(7)  for information on how to determine whether an error has occurred when
       calling these functions.

       The following errors can occur:

       Range error: result overflow
              errno is set to ERANGE.  An  overflow  floating-point  exception  (FE_OVERFLOW)  is
              raised.

       Range error: result underflow
              An underflow floating-point exception (FE_UNDERFLOW) is raised.

              These functions do not set errno for this case.

CONFORMING TO
       C99, POSIX.1-2001.  The variant returning double also conforms to SVr4, 4.3BSD.

SEE ALSO
       cabs(3), sqrt(3)

COLOPHON
       This  page  is  part of release 3.74 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of  this  page,  can  be
       found at http://www.kernel.org/doc/man-pages/.



                                            2010-09-20                                   HYPOT(3)