Exemplo n.º 1
0
double
__cbrt (double x)
{
  double xm, ym, u, t2;
  int xe;

  /* Reduce X.  XM now is an range 1.0 to 0.5.  */
  xm = __frexp (fabs (x), &xe);

  /* If X is not finite or is null return it (with raising exceptions
     if necessary.
     Note: *Our* version of `frexp' sets XE to zero if the argument is
     Inf or NaN.  This is not portable but faster.  */
  if (xe == 0 && fpclassify (x) <= FP_ZERO)
    return x + x;

 u = (0.354895765043919860
      + ((1.50819193781584896
	 + ((-2.11499494167371287
	    + ((2.44693122563534430
	       + ((-1.83469277483613086
		  + (0.784932344976639262 - 0.145263899385486377 * xm) * xm)
		  * xm))
	       * xm))
	    * xm))
	 * xm));

  t2 = u * u * u;

  ym = u * (t2 + 2.0 * xm) / (2.0 * t2 + xm) * factor[2 + xe % 3];

  return __ldexp (x > 0.0 ? ym : -ym, xe / 3);
}
Exemplo n.º 2
0
Err mathlib_ldexp(UInt16 refnum, double x, Int16 exponent, double *result) {
#pragma unused(refnum)
	*result = __ldexp(x, exponent);
	return mlErrNone;
}