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man:hypot

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():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| _XOPEN_SOURCE
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
hypotf(), hypotl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE```

DESCRIPTION

```     These  functions  return  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  trian-
gle 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.`

ATTRIBUTES

```     For   an   explanation   of   the  terms  used  in  this  section,  see
attributes(7).```
```     +----------------------------+---------------+---------+
|Interface                   | Attribute     | Value   |
+----------------------------+---------------+---------+
|hypot(), hypotf(), hypotl() | Thread safety | MT-Safe |
+----------------------------+---------------+---------+```

CONFORMING TO

`     C99, POSIX.1-2001, POSIX.1-2008.`
`     The variant returning double also conforms to SVr4, 4.3BSD.`

`     cabs(3), sqrt(3)`
```     This  page  is  part of release 4.16 of the Linux man-pages project.  A
`                                2017-09-15                          HYPOT(3)`