Mathematical Library Functions ldexp(3M)
NAME
ldexp, ldexpf, ldexpl - load exponent of a floating point
numberSYNOPSIS
c99 [ flag... ] file... -lm [ library... ]
#include
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 multi-
plied by 2 raised to the power exp. If these functions would cause overflow, a range erroroccurs 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.SunOS 5.11 Last change: 12 Jul 2006 1
Mathematical Library Functions ldexp(3M)USAGE
An application wanting to check for exceptions should callfeclearexcept(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 callingldexp(). 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 attri-
butes:____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Interface Stability | Committed ||_____________________________|_____________________________|
| MT-Level | MT-Safe |
|_____________________________|_____________________________|
| Standard | See standards(5). ||_____________________________|_____________________________|
SEE ALSO
frexp(3M), isnan(3M), modf(3M), attributes(5), standards(5)SunOS 5.11 Last change: 12 Jul 2006 2