SCALB(3) Library Functions Manual SCALB(3)

scalbload exponent of a radix-independent floating-point number

#include <math.h>

double scalb(double x, double n);

The scalb() function computes x * r n , where r is the radix of the machine's floating point arithmetic. When r is 2, scalb() is equivalent to ldexp(3) .

An application wishing to check for error situations should set errno to 0 before calling scalb(). If errno is non-zero on return, or the return value is NaN, an error has occurred.

Upon successful completion, the scalb() function returns x * r n .

If the correct value would overflow, scalb() returns ±HUGE_VAL (according to the sign of x) and sets errno to [ERANGE].

If the correct value would underflow, scalb() returns 0 and sets errno to [ERANGE].

The scalb() function returns x when x is ±Inf.

If x or n is NaN, then scalb() returns NaN and may set errno to [EDOM].

The scalb() function will fail if:

The correct value would overflow or underflow.

The scalb() function may fail if:

The x or n argument is NaN.

None.

None.

None.

ldexp(3) , <math.h> .

February 1997 posix.fail