fma(3) BSD Library Functions Manual fma(3)
NAME
     fma -- multiply and add, then round
SYNOPSIS
     #include <math.h>
     double
     fma(double x, double y, double z);
     long double
     fmal(long double x, long double y, long double z);
     float
     fmaf(float x, float y, float z);
DESCRIPTION
     The fma() functions compute (x*y)+z, rounded as one ternary operation:
     they compute the value (as if) to infinite precision and round once to
     the result format, according to the current rounding mode.
SPECIAL VALUES
     fma(x, y, z) returns a NaN and optionally raises the "invalid" floating-
     point exception if one of x and y is infinite, the other is 0, and z is a
     NaN.
     fma(x, y, z) returns a NaN and raises the "invalid" floating-point excep-
     tion if one of x and y is infinite, the other is 0, and z is not NaN.
     fma(x, y, z) returns a NaN and raises the "invalid" floating-point excep-
     tion if x times y is an exact infinity, and z is also an infinity but
     with the opposite sign.
SEE ALSO
     fdim(3), fmax(3), fmin(3)
STANDARDS
     The fma() functions conform to ISO/IEC 9899:2011.
BSD                              May 28, 2008                              BSD
Mac OS X 10.9.1 - Generated Wed Jan 8 06:17:01 CST 2014
