Synopsis
#include <math.h>
double scalbn(double x, int exp);
Description

scalbn multiplies a floating-point number by an integral power of FLT_RADIX.

As floating-point aritmetic conforms to IEC 60559, FLT_RADIX is 2 and scalbn is (in this implementation) identical to ldexp.

scalbn returns x * FLT_RADIX^exp.

Fast math library behavior

If the result overflows, errno is set to ERANGE and scalbn returns HUGE_VAL.

IEC 60559 math library behavior

If x is ∞ or NaN, scalbn returns x.
If the result overflows, scalbn returns ∞.

Portability

scalbn conforms to ISO/IEC 9899:1999 (C99).

See Also

ldexp