|FMA(3)||Linux Programmer's Manual||FMA(3)|
NAMEfma, fmaf, fmal - floating-point multiply and add
double fma(double x , double y , double z );
float fmaf(float x , float y , float z );
long double fmal(long double x , long double y , long double z );
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
_XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;or cc -std=c99
DESCRIPTIONThe fma() function computes x * y + z. The result is rounded as one ternary operation according to the current rounding mode (see fenv(3)).
RETURN VALUEThese functions return the value of x * y + z, rounded as one ternary operation.
ERRORSSee math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
- Domain error: x * y + z, or x * y is invalid and z is not a NaN
- An invalid floating-point exception ( FE_INVALID) is raised.
- Range error: result overflow
- 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.
VERSIONSThese functions first appeared in glibc in version 2.1.
CONFORMING TOC99, POSIX.1-2001.
SEE ALSOremainder(3), remquo(3)
COLOPHONThis page is part of release 3.53 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/.