'\" t .\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de) .\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk .\" .\" .\" SPDX-License-Identifier: GPL-1.0-or-later .\" .TH fmax 3 2024-05-02 "Linux man-pages 6.8" .SH NAME fmax, fmaxf, fmaxl \- determine maximum of two floating-point numbers .SH LIBRARY Math library .RI ( libm ", " \-lm ) .SH SYNOPSIS .nf .B #include .P .BI "double fmax(double " x ", double " y ); .BI "float fmaxf(float " x ", float " y ); .BI "long double fmaxl(long double " x ", long double " y ); .fi .P .RS -4 Feature Test Macro Requirements for glibc (see .BR feature_test_macros (7)): .RE .P .BR fmax (), .BR fmaxf (), .BR fmaxl (): .nf _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L .fi .SH DESCRIPTION These functions return the larger value of .I x and .IR y . .SH RETURN VALUE These functions return the maximum of .I x and .IR y . .P If one argument is a NaN, the other argument is returned. .P If both arguments are NaN, a NaN is returned. .SH ERRORS No errors occur. .SH ATTRIBUTES For an explanation of the terms used in this section, see .BR attributes (7). .TS allbox; lbx lb lb l l l. Interface Attribute Value T{ .na .nh .BR fmax (), .BR fmaxf (), .BR fmaxl () T} Thread safety MT-Safe .TE .SH STANDARDS C11, POSIX.1-2008. .SH HISTORY glibc 2.1. C99, POSIX.1-2001. .SH SEE ALSO .BR fdim (3), .BR fmin (3)