FMA(3) Linux Programmer s Manual FMA(3)
NAME fma, fmaf, fmal - floating-point multiply and add
SYNOPSIS #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);
Compile with -std=c99; link with -lm.
DESCRIPTION The fma() function computes x * y + z. The result is rounded according to the rounding mode determined by the value of FLT_ROUNDS. FLT_ROUNDS indicates the implementation-defined rounding behaviour for floating- point addition, and has one of the following values:
-1 The rounding mode is not determinable.
0 Rounding is towards 0.
1 Rounding is towards nearest number.
2 Rounding is towards positive infinity.
3 Rounding is towards negative infinity.
Other values represent machine-dependent, non-standard rounding modes.
CONFORMING TO C99
SEE ALSO fenv(3), remainder(3), remquo(3)