#include <math.h>float scalblnf(float val, long int exp);double scalbln(double val, long int exp); long double scalblnl(long double val, long int exp);
scalbln( ), scalblnf( ), and scalblnl( ) were added by C99.
The scalbln( ) family of functions returns the product of val and FLT_RADIX raised to the exp power. That is,
val * FLT_RADIXexp
The macro FLT_RADIX is defined in <float.h> and its value is the radix of exponent representation.
A related function is scalbn( ).