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);
```

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
```

_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

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.

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.

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.

For an explanation of the terms used in this section, see attributes(7).

Interface | Attribute | Value |

hypot(), hypotf(), hypotl() | Thread safety | MT-Safe |

C99, POSIX.1-2001, POSIX.1-2008.

The variant returning `double`

also conforms to SVr4, 4.3BSD.

This page is part of release 4.15 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 https://www.kernel.org/doc/man-pages/.