NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | VERSIONS | ATTRIBUTES | CONFORMING TO | SEE ALSO | COLOPHON |

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FMA(3) Linux Programmer's Manual FMA(3)
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fma, fmaf, fmal - floating-point multiply and add

#include <math.h>double fma(doublex, doubley, doublez);float fmaf(floatx, floaty, floatz);long double fmal(long doublex, long doubley, long doublez);Link with-lm. Feature Test Macro Requirements for glibc (see feature_test_macros(7)):fma(),fmaf(),fmal(): _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

These functions computex*y+z. The result is rounded as one ternary operation according to the current rounding mode (see fenv(3)).

These functions return the value ofx*y+z, rounded as one ternary operation. Ifxoryis a NaN, a NaN is returned. Ifxtimesyis an exact infinity, andzis an infinity with the opposite sign, a domain error occurs, and a NaN is returned. If one ofxoryis an infinity, the other is 0, andzis not a NaN, a domain error occurs, and a NaN is returned. If one ofxoryis an infinity, and the other is 0, andzis a NaN, a domain error occurs, and a NaN is returned. Ifxtimesyis not an infinity times zero (or vice versa), andzis 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: Domain error:x*y+z, orx*yis invalid andzis not a NaN An invalid floating-point exception (FE_INVALID) is raised. Range error: result overflow An overflow floating-point exception (FE_OVERFLOW) is raised. Range error: result underflow An underflow floating-point exception (FE_UNDERFLOW) is raised. These functions do not seterrno.

These functions first appeared in glibc in version 2.1.

For an explanation of the terms used in this section, see attributes(7). ┌──────────────────────┬───────────────┬─────────┐ │Interface│Attribute│Value│ ├──────────────────────┼───────────────┼─────────┤ │fma(),fmaf(),fmal() │ Thread safety │ MT-Safe │ └──────────────────────┴───────────────┴─────────┘

C99, POSIX.1-2001, POSIX.1-2008.

remainder(3), remquo(3)

This page is part of release 4.12 of the Linuxman-pagesproject. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/. 2016-03-15 FMA(3)