fma

fma, fmaf, fmal - floating-point multiply and add

#include <math.h>
 I double fma(double  x , double  y , double  z );

I float fmaf(float  x , float  y , float  z );

I long double fmal(long double  x , long double  y , long double  z );

Compile with -std=c99; link with -lm.

The R fma () function computes R x * y + z . The result is rounded according to the rounding mode determined by the value of R FLT_ROUNDS . FLT_ROUNDS indicates the implementation-defined rounding behavior for floating-point addition, and has one of the following values:

-1 The rounding mode is not determinable.

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.

C99

fenv(3), remainder(3), remquo(3)