frexp
break floating-point number into normalized fraction and power of 2
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NAME
<span class="Nm" id="frexp">frexp</span>
INTERFACE
#include <math.h>
double frexp ( double value, int *exp ) long frexpl ( long double value, int *exp ) float frexpf ( float value, int *exp )
DESCRIPTION
The frexp functions break the floating-point number \c value into a normalized fraction and an integral power of 2. They store the integer in the int object pointed to by \c exp. \n \n The functions return a number x such that x has a magnitude in the interval [1/2, 1) or 0, and value = x*(2**exp).
SPECIAL VALUES
frexp ( <span class="Fn">�0</span>, <span class="Fn">exp</span> ) returns �0, and stores 0 in the object pointed to by exp. \n \n frexp ( <span class="Fn">�infinity</span>, <span class="Fn">exp</span> ) returns �infinity, and stores an unspecified value in the object pointed to by exp. \n \n frexp ( <span class="Fn">Nan</span>, <span class="Fn">exp</span> ) returns a Nan, and stores an unspecified value in the object pointed to by exp.
SEE ALSO
reference:math (3) , reference:scalbn
STANDARDS
The frexp functions conform to ISO/IEC 9899:1999(E).