std::ldexp

 

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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       ldexp( float x, int exp );
double      ldexp( double x, int exp );
long double ldexp( long double x, int exp );
double      ldexp( Integral x, int exp );		(since C++11)

Multiplies a floating point value x by 2 raised to power exp.

Parameters

x	-	floating point value
exp	-	integer value

Return value

returns x × 2exp

If the result is too large for the underlying type, range error occurs and HUGE_VAL is returned.

See also

frexp	decomposes a number into significand and a power of 2 (function)
scalbnscalbln (C++11)(C++11)	multiplies a number by FLT_RADIX raised to a power (function)
C documentation for ldexp