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       ldexp,  ldexpf,  ldexpl  -  multiply  floating-point number by integral
       power of 2


       #include <math.h>

       double ldexp(double x, int exp);
       float ldexpf(float x, int exp);
       long double ldexpl(long double x, int exp);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       ldexpf(), ldexpl(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600
       || _ISOC99_SOURCE; or cc -std=c99


       The  ldexp()  function  returns the result of multiplying the floating-
       point number x by 2 raised to the power exp.


       On success, these functions return x * (2^exp).

       If exp is zero, then x is returned.

       If x is a NaN, a NaN is returned.

       If x  is  positive  infinity  (negative  infinity),  positive  infinity
       (negative infinity) is returned.

       If the result underflows, an  range error occurs, and zero is returned.

       If the result overflows, a range error occurs, and the functions return
       HUGE_VAL,  HUGE_VALF,  or HUGE_VALL, respectively, with a sign the same
       as x.


       See math_error(7) for information on how to determine whether an  error
       has occurred when calling these functions.

       The following errors can occur:

       Range error, overflow
              errno  is  set  to ERANGE.  An overflow floating-point exception
              (FE_OVERFLOW) is raised.

       Range error, underflow
              errno is set to ERANGE.  An underflow  floating-point  exception
              (FE_UNDERFLOW) is raised.


       C99, POSIX.1-2001.  The variant returning double also conforms to SVr4,
       4.3BSD, C89.


       frexp(3), modf(3), scalbln(3)


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                                  2008-08-05                          LDEXP(3)