frexp(3C) — sysv — mips UMIPS RISC/os 4.52



FREXP(3C-SysV)      RISC/os Reference Manual       FREXP(3C-SysV)



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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