std::scalbn, std::scalbln

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Defined in header <cmath>
float       scalbn( float x, int exp );		(C++11 feature)
double      scalbn( double x, int exp );		(C++11 feature)
long double scalbn( long double x, int exp );		(C++11 feature)
float       scalbln( float x, long exp );		(C++11 feature)
double      scalbln( double x, long exp );		(C++11 feature)
long double scalbln( long double x, long exp );		(C++11 feature)

Multiplies an floating point value x by FLT_RADIX raised to power exp. On binary system it is equivalent to ldexp()

[edit] Parameters

arg	-	floating point value
exp	-	integer value

[edit] Return value

returns x×FLT_RADIX^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)
ldexp	multiplies a number by 2 raised to a power (function)