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

## NAME         top

```       hypot, hypotf, hypotl - Euclidean distance function
```

## SYNOPSIS         top

```       #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)):

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         top

```       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         top

```       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         top

```       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         top

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

```       cabs(3), sqrt(3)
```

## COLOPHON         top

```       This page is part of release 3.51 of the Linux man-pages project.  A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.

2010-09-20                         HYPOT(3)
```