std::trunc

 

C++

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Basic operations
abs(int) labs llabs imaxabs (C++11) abs(float) fabs div ldiv lldiv imaxdiv (C++11) fmod	remainder (C++11) remquo (C++11) fma (C++11) fmax (C++11) fmin (C++11) fdim (C++11) nan nanf nanl (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 round lround llround (C++11) (C++11) (C++11)	trunc (C++11) nearbyint (C++11) rint lrint llrint (C++11) (C++11) (C++11)
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ldexp scalbn scalbln (C++11) (C++11) ilogb (C++11) logb (C++11)	frexp modf nextafter nexttoward (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)
Macro constants
HUGE_VALF HUGE_VAL HUGE_VALL (C++11) (C++11) INFINITY (C++11) NAN (C++11) math_errhandling MATH_ERRNO MATH_ERREXCEPT (C++11)	FP_NORMAL FP_SUBNORMAL FP_ZERO FP_INFINITE FP_NAN (C++11) (C++11) (C++11) (C++11) (C++11) FLT_EVAL_METHOD (C++11)

 

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

Computes nearest integer not greater in magnitude than arg.

Parameters

arg

-

floating point value

Return value

Nearest integer not greater in magnitude than arg.

Return value

Argument

Notes

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

See also

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