opensolaris man page for ldexp

Query: ldexp

OS: opensolaris

Section: 3m

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ldexp(3M)						  Mathematical Library Functions						 ldexp(3M)

NAME
ldexp, ldexpf, ldexpl - load exponent of a floating point number
SYNOPSIS
c99 [ flag... ] file... -lm [ library... ] #include <math.h> double ldexp(double x, int exp); float ldexpf(float x, int exp); long double ldexpl(long double x, int exp);
DESCRIPTION
These functions computes the quantity x* 2^exp.
RETURN VALUES
Upon successful completion, these functions return x multiplied by 2 raised to the power exp. If these functions would cause overflow, a range error occurs and ldexp(), ldexpf(), and ldexpl() return +-HUGE_VAL, +-HUGE_VALF, and +-HUGE_VALL (according to the sign of x), respectively. If x is NaN, a NaN is returned. If x is +-0 or +-Inf, x is returned. If exp is 0, x is returned.
ERRORS
These functions will fail if: Range Error The result overflows. If the integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, the overflow floating-point exception is raised. The ldexp() function sets errno to ERANGE if the result overflows.
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 ldexp(). On return, if errno is non-zero, an error has occurred. The ldexpf() and ldexpl() 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
frexp(3M), isnan(3M), modf(3M), attributes(5), standards(5) SunOS 5.11 12 Jul 2006 ldexp(3M)