scalb(3M)

NAME

     scalb - load exponent of a radix-independent  floating-point
     number

SYNOPSIS

     #include <math.h>

     double scalb(double x, double n);

DESCRIPTION

     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(3C).

RETURN VALUES

     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 to 0.0, 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.

     For exceptional cases, matherr(3M) tabulates the  values  to
     be returned as dictated by Standards other than XPG4.

ERRORS

     The scalb() function will fail if:

     ERANGE
           The correct value would overflow or underflow.

USAGE

     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.

ATTRIBUTES

     See attributes(5) for descriptions of the  following  attri-
     butes:

     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | MT-Level                    | MT-Safe                     |
    |_____________________________|_____________________________|

SEE ALSO

     ldexp(3C), matherr(3M), attributes(5)