std::ldexp

From Cppreference

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Defined in header <cmath>
float       ldexp( float arg, int exp );
double      ldexp( double arg, int exp );
long double ldexp( long double arg, int exp );
double      ldexp( Integral arg, int exp );		(since C++11)

Multiplies an floating point value arg by 2 raised to power exp.

[edit] Parameters

arg	-	floating point value
exp	-	integer value

[edit] Return value

returns x×2^exp

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

[edit] See also

frexp	decomposes a number into significand and a power of 2 (function)
scalbn scalbln (C++11) (C++11)	multiplies a number by FLT_RADIX raised to a power (function)