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std::fmax,std::fmaxf,std::fmaxl(3) C++ Standard Libary std::fmax,std::fmaxf,std::fmaxl(3)


std::fmax,std::fmaxf,std::fmaxl - std::fmax,std::fmaxf,std::fmaxl


Defined in header <cmath>
float fmax ( float x, float y ); (1) (since C++11)
(constexpr since C++23)
float fmaxf( float x, float y ); (2) (since C++11)
(constexpr since C++23)
double fmax ( double x, double y ); (3) (since C++11)
(constexpr since C++23)
long double fmax ( long double x, long double y ); (4) (since C++11)
(constexpr since C++23)
long double fmaxl( long double x, long double y ); (5) (since C++11)
(constexpr since C++23)
Promoted fmax ( Arithmetic1 x, Arithmetic2 y ); (6) (since C++11)
(constexpr since C++23)

1-5) Returns the larger of two floating point arguments, treating NaNs as missing
data (between a NaN and a numeric value, the numeric value is chosen)
6) A set of overloads or a function template for all combinations of arguments of
arithmetic type not covered by (1-5). If any argument has integral type, it is cast
to double. If any other argument is long double, then the return type is long
double, otherwise it is double.


x, y - values of floating-point or integral types

Return value

If successful, returns the larger of two floating point values. The value returned
is exact and does not depend on any rounding modes.

Error handling

This function is not subject to any of the error conditions specified in

If the implementation supports IEEE floating-point arithmetic (IEC 60559),

* If one of the two arguments is NaN, the value of the other argument is returned
* Only if both arguments are NaN, NaN is returned


This function is not required to be sensitive to the sign of zero, although some
implementations additionally enforce that if one argument is +0 and the other is -0,
then +0 is returned.


// Run this code

#include <iostream>
#include <cmath>

int main()
std::cout << "fmax(2,1) = " << std::fmax(2,1) << '\n'
<< "fmax(-Inf,0) = " << std::fmax(-INFINITY,0) << '\n'
<< "fmax(NaN,-1) = " << std::fmax(NAN,-1) << '\n';


fmax(2,1) = 2
fmax(-Inf,0) = 0
fmax(NaN,-1) = -1

See also

isgreater checks if the first floating-point argument is greater than the
(C++11) second
fminl smaller of two floating point values
(C++11) (function)
max returns the greater of the given values
(function template)
max_element returns the largest element in a range
(function template)
minmax returns the smaller and larger of two elements
(C++11) (function template)
minmax_element returns the smallest and the largest elements in a range
(C++11) (function template)