FMA(3) BSD Library Functions Manual FMA(3)

NAME
     ffmmaa - multiply and add, then round

SYNOPSIS
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     double
     ffmmaa(double x, double y, double z);

     long double
     ffmmaall(long double x, long double y, long double z);

     float
     ffmmaaff(float x, float y, double z);

DESCRIPTION
     The ffmmaa() 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.

SSPPEECCIIAALL VVAALLUUEESS
     ffmmaa(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.

     ffmmaa(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.

     ffmmaa(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 ffmmaa() functions conform to ISO/IEC 9899:1999(E).

BSD                              July 24, 2003                             BSD