fdim(3) - BetterMan

fdim(3)

positive difference

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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
);
fdimf
(), 
fdiml
():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

—

Options · 1

Range error: result overflow

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

NAME

fdim, fdimf, fdiml - positive difference

LIBRARY

Math library (libm, -lm)

SYNOPSIS

bash

#include <math.h>

bash

double fdim(double \nx\n, double \ny\n);\n
\nfloat fdimf(float \nx\n, float \ny\n);\n
\nlong double fdiml(long double \nx\n, long double \ny\n);

fdimf(), fdiml():

bash


\n
    _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:

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

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

C11, POSIX.1-2008.

HISTORY

glibc 2.1. C99, POSIX.1-2001.

BUGS

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