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/* @(#)z_numtestf.c 1.0 98/08/13 */

/******************************************************************

 * Numtest

 *

 * Input:

 *   x - pointer to a floating point value

 *

 * Output:

 *   An integer that indicates what kind of number was passed in:

 *     NUM = 3 - a finite value

 *     NAN = 2 - not a number

 *     INF = 1 - an infinite value

 *           0 - zero

 *

 * Description:

 *   This routine returns an integer that indicates the character-

 *   istics of the number that was passed in.

 *

 *****************************************************************/

#include "fdlibm.h"

#include "zmath.h"

int

_DEFUN (numtestf, (float),

        float x)

{

  __int32_t wx;

  int exp;

  GET_FLOAT_WORD (wx, x);

  exp = (wx & 0x7f800000) >> 23;

  /* Check for a zero input. */

  if (x == 0.0)

    {

      return (0);

    }

  /* Check for not a number or infinity. */

  if (exp == 0x7f8)

    {

      if(wx & 0x7fffff)

        return (NAN);

      else

        return (INF);

    }

  /* Otherwise it's a finite value. */

  else

    return (NUM);

}

#ifdef _DOUBLE_IS_32BITS

int numtest (double x)

{

  return numtestf ((float) x);

}

#endif /* defined(_DOUBLE_IS_32BITS) */