hypot, hypotf, hypotl - Euclidean distance function
#include <math.h> double hypot(double x, double y); float hypotf(float x, float y); long double hypotl(long double x, long double y);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
These functions return
y). This is the length of
the hypotenuse of a right-angled triangle with sides of length
y, or the distance of the point
y) from the origin.
The calculation is performed without undue overflow or underflow during the intermediate steps of the calculation.
On success, these functions return the length of the hypotenuse of a
right-angled triangle with sides of length
y is an infinity, positive infinity is
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.
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
errno is set to ERANGE. An overflow
floating-point exception (FE_OVERFLOW) is raised.
An underflow floating-point exception (FE_UNDERFLOW) is raised.
These functions do not set
errno for this case.
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning
double also conforms to SVr4,
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