std::floor

 

C++

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Functions
Basic operations
abs(int)labsllabsimaxabs (C++11) abs(float)fabs divldivlldivimaxdiv (C++11) fmod	remainder (C++11) remquo (C++11) fma (C++11) fmax (C++11) fmin (C++11) fdim (C++11) nannanfnanl (C++11)(C++11)(C++11)
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erf (C++11) erfc (C++11)	lgamma (C++11) tgamma (C++11)
Nearest integer floating point operations
ceil floor roundlroundllround (C++11)(C++11)(C++11)	trunc (C++11) nearbyint (C++11) rintlrintllrint (C++11)(C++11)(C++11)
Floating point manipulation functions
ldexp scalbnscalbln (C++11)(C++11) ilogb (C++11) logb (C++11)	frexp modf nextafternexttoward (C++11)(C++11) copysign (C++11)
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fpclassify (C++11) isfinite (C++11) isinf (C++11) isnan (C++11) isnormal (C++11) signbit (C++11)	isgreater (C++11) isgreaterequal (C++11) isless (C++11) islessequal (C++11) islessgreater (C++11) isunordered (C++11)
Macro constants
HUGE_VALFHUGE_VALHUGE_VALL (C++11)(C++11) INFINITY (C++11) NAN (C++11) math_errhandlingMATH_ERRNOMATH_ERREXCEPT (C++11)	FP_NORMALFP_SUBNORMALFP_ZEROFP_INFINITEFP_NAN (C++11)(C++11)(C++11)(C++11)(C++11)

 

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

Run this code

#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)
roundlroundllround (C++11)(C++11)(C++11)	nearest integer, rounding away from zero in halfway cases (function)