fma, fmaf, fmal - floating-point multiply and add
#include <math.h> 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)):
These functions compute
result is rounded as one ternary operation according to the current
rounding mode (see fenv(3)).
These functions return the value of
z, rounded as one ternary operation.
y is a NaN, a NaN is returned.
y is an exact infinity, and
is an infinity with the opposite sign, a domain error occurs, and a NaN
If one of
y is an infinity, the other is 0,
z is not a NaN, a domain error occurs, and a NaN is
If one of
y is an infinity, and the other is
z is a NaN, a domain error occurs, and a NaN is
y is not an infinity times zero (or vice
z is a NaN, a NaN is returned.
If the result overflows, a range error occurs, and an infinity with the correct sign is returned.
If the result underflows, a range error occurs, and a signed 0 is returned.
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
yis invalid and
zis not a NaN
An invalid floating-point exception (FE_INVALID) is raised.
An overflow floating-point exception (FE_OVERFLOW) is raised.
An underflow floating-point exception (FE_UNDERFLOW) is raised.
These functions do not set
These functions first appeared in glibc in version 2.1.
C99, POSIX.1-2001, POSIX.1-2008.
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