std::floor

 

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Defined in header <cmath>
float       floor( float arg );
double      floor( double arg );
long double floor( long double arg );
double      floor( Integral arg );		(since C++11)

Computes nearest integer not greater than arg.

Parameters

arg

-

floating point value

Return value

Nearest integer not greater than arg

Return value

Argument

Notes

The integer value can be always represented by the given floating point type.

Example

#include <cmath>
#include <iostream>
 
int main()
{
    std::cout << std::fixed;
    std::cout << std::floor(12.0) << '\n';
    std::cout << std::floor(12.1) << '\n';
    std::cout << std::floor(12.5) << '\n';
    std::cout << std::floor(12.9) << '\n';
    std::cout << std::floor(13.0) << '\n';
}

Output:

12.000000
12.000000
12.000000
12.000000
13.000000

See also

ceil	nearest integer not less than the given value (function)
trunc (C++11)	nearest integer not greater in magnitude than the given value (function)
round lround llround (C++11) (C++11) (C++11)	nearest integer, rounding away from zero in halfway cases (function)