scalb(3m) [sunos man page]

scalb(3M)						  Mathematical Library Functions						 scalb(3M)

NAME

       scalb, scalbf, scalbl - load exponent of a radix-independent floating-point number

SYNOPSIS

       cc [ flag... ] file... -lm [ library... ]
       #include <math.h>

       double scalb(double x, double n);

       float scalbf(float x, float n);

       long double scalbl(long double x, long double n);

DESCRIPTION

       These  functions  compute  x * r**n, where r is the radix of the machine's floating point arithmetic. When r is 2, scalb() is equivalent to
       ldexp(3M). The value of r is FLT_RADIX which is defined in <float.h>.

RETURN VALUES

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

       If x or n is NaN, a NaN is returned.

       If n is 0, x is returned.

       If x is +-Inf and n is not -Inf, x is returned.

       If x is +-0 and n is not +Inf, x is returned.

       If x is +-0 and n is +Inf, a domain error occurs and a NaN is returned.

       If x is +-Inf and n is -Inf, a domain error occurs and a NaN is returned.

       If the result would cause an overflow, a range error occurs and +-HUGE_VAL (according to the sign of x) is returned.

       For exceptional cases, matherr(3M) tabulates the values to be returned by scalb() as specified by SVID3 and XPG3. See standards(5).

ERRORS

       These functions will fail if:

       Domain Error    If x is 0 and n is +Inf, or x is Inf and n is -Inf.

		       If the integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, then the  invalid  floating-point  exception	is
		       raised.

       Range Error     The result would overflow.

		       If  the	integer  expression (math_errhandling & MATH_ERREXCEPT) is non-zero, then the overflow floating-point exception is
		       raised.

USAGE

       An application wanting to check for exceptions should call feclearexcept(FE_ALL_EXCEPT) before  calling	these  functions.  On  return,	if
       fetestexcept(FE_INVALID	|  FE_DIVBYZERO  |  FE_OVERFLOW  |  FE_UNDERFLOW) is non-zero, an exception has been raised. An application should
       either examine the return value or check the floating point exception flags to detect exceptions.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |See below.		   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

       The scalb() function is Standard. The scalbf() and scalbl() functions are Stable.

SEE ALSO

       feclearexcept(3M), fetestexcept(3M), ilogb(3M), ldexp(3M), logb(3M), math.h(3HEAD), matherr(3M), scalbln(3M), attributes(5), standards(5)

SunOS 5.10							    1 Nov 2003								 scalb(3M)

Check Out this Related Man Page

logb(3M)						  Mathematical Library Functions						  logb(3M)

NAME

       logb, logbf, logbl - radix-independent exponent

SYNOPSIS

       cc [ flag... ] file... -lm [ library... ]
       #include <math.h>

       double logb(double x);

       float logbf(float x);

       long double logbl(long double x);

DESCRIPTION

       These  functions compute the exponent of x, which is the integral part of logr |x|, as a signed floating point value, for non-zero x, where
       r is the radix of the machine's floating-point arithmetic, which is the value of FLT_RADIX defined in the <float.h> header.

RETURN VALUES

       Upon successful completion, these functions return the exponent of x.

       If x is subnormal:

	 o  For SUSv3-conforming applications (see standards(5)), the exponent of x as if x were normalized is returned.

	 o  Otherwise, -1022, -126, and -16382 are returned for logb(), logbf(), and logbl(), respectively.

       If x is +-0, a pole error occurs and logb(), logbf(), and logbl() return -HUGE_VAL, -HUGE_VALF, and -HUGE_VALL, respectively.

       If x is NaN, a NaN is returned.

       If x is +-Inf, +Inf is returned.

ERRORS

       These functions will fail if:

       Pole Error      The value of x is +-0.

		       If the integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, the divide-by-zero floating-point  exception	is
		       raised.

		       The logb() function sets errno to EDOM if the value of x is 0.

USAGE

       An  application	wanting  to  check  for  exceptions should call feclearexcept(FE_ALL_EXCEPT) before calling these functions. On return, if
       fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an exception  has  been  raised.  An  application  should
       either examine the return value or check the floating point exception flags to detect exceptions.

       An  application	can  also  set	errno  to 0 before calling logb(). On return, if errno is non-zero, an error has occurred. The logbf() and
       logbl() functions do not set errno.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       feclearexcept(3M), fetestexcept(3M), ilogb(3M), math.h(3HEAD), matherr(3M), scalb(3M), attributes(5), standards(5)

SunOS 5.10							    1 Nov 2003								  logb(3M)

Linux and UNIX Man Pages

scalb(3m) [sunos man page]

Check Out this Related Man Page