# fdiml(3) [freebsd man page]

```FDIM(3) 						   BSD Library Functions Manual 						   FDIM(3)

NAME
fdim, fdimf, fdiml -- positive difference functions

LIBRARY
Math Library (libm, -lm)

SYNOPSIS
#include <math.h>

double
fdim(double x, double y);

float
fdimf(float x, float y);

long double
fdiml(long double x, long double y);

DESCRIPTION
The fdim(), fdimf(), and fdiml() functions return the positive difference between x and y.  That is, if x-y is positive, then x-y is
returned.	If either x or y is an NaN, then an NaN is returned.  Otherwise, the result is +0.0.

Overflow or underflow may occur if the exact result is not representable in the return type.  No other exceptions are raised.

fabs(3), fmax(3), fmin(3), math(3)

STANDARDS
The fdim(), fdimf(), and fdiml() functions conform to ISO/IEC 9899:1999 (``ISO C99'').

HISTORY
These routines first appeared in FreeBSD 5.3.

BSD								   June 29, 2004							       BSD```

## Check Out this Related Man Page

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

NAME
fdim, fdimf, fdiml - positive difference

SYNOPSIS
#include <math.h>

double fdim(double x, double y);
float fdimf(float x, float y);
long double fdiml(long double x, long double y);

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

fdimf(), fdiml(): _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or cc -std=c99

DESCRIPTION
These functions return the positive difference, max(x-y,0), between their arguments.

RETURN VALUE
On success, these functions return the positive difference.

If x or y is a NaN, a NaN is returned.

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

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
An overflow floating-point exception (FE_OVERFLOW) is raised.

These functions do not set errno.

VERSIONS
These functions first appeared in glibc in version 2.1.

CONFORMING TO
C99, POSIX.1-2001.

fmax(3)

COLOPHON
This  page is part of release 3.25 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/.

2008-08-11								   FDIM(3)```
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