frexp(3C) — Interactive 2.2



          FREXP(3C)            INTERACTIVE UNIX System            FREXP(3C)



          NAME
               frexp, ldexp, modf - manipulate parts of floating-point
               numbers

          SYNOPSIS
               double frexp (value, eptr)
               double value;
               int *eptr;

               double ldexp (value, exp)
               double value;
               int exp;

               double modf (value, iptr)
               double value, *iptr;

          DESCRIPTION
               Every non-zero number can be written uniquely as x* 2n,
               where the ``mantissa'' (fraction) x is in the range 0.5 <
               |x| < 1.0, and the ``exponent'' n is an integer.  frexp
               returns the mantissa of a double value and stores the
               exponent indirectly in the location pointed to by eptr.  If
               value is zero, both results returned by frexp are zero.

               Ldexp returns the quantity value* 2exp.

               Modf returns the signed fractional part of value and stores
               the integral part indirectly in the location pointed to by
               iptr.

          DIAGNOSTICS
               If ldexp would cause overflow, +HUGE (defined in <math.h> )
               is returned (according to the sign of value), and errno is
               set to ERANGE.
               If ldexp would cause underflow, zero is returned and errno
               is set to ERANGE.



















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