Scroll to navigation

FDIM(3) Library Functions Manual FDIM(3)

NAME

fdim, fdimf, fdiml - positive difference

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);

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

fdimf(), fdiml():


_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

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:

errno is set to ERANGE. An overflow floating-point exception (FE_OVERFLOW) is raised.

VERSIONS

These functions first appeared in glibc in version 2.1.

ATTRIBUTES

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

Interface Attribute Value
fdim (), fdimf (), fdiml () Thread safety MT-Safe

STANDARDS

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

BUGS

Before glibc version 2.24 on certain architectures (e.g., x86, but not x86_64) these functions did not set errno.

SEE ALSO

fmax(3)

2022-10-09 Linux man-pages 6.01