/* -*- c++ -*- */

/*

 * Copyright 2003 Free Software Foundation, Inc.

 * 

 * This file is part of GNU Radio

 * 

 * GNU Radio is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 3, or (at your option)

 * any later version.

 * 

 * GNU Radio is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 * 

 * You should have received a copy of the GNU General Public License

 * along with GNU Radio; see the file COPYING.  If not, write to

 * the Free Software Foundation, Inc., 51 Franklin Street,

 * Boston, MA 02110-1301, USA.

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <gr_math.h>

#include <math.h>

/*

 * Greatest Common Divisor, using Euclid's algorithm.

 * [There are faster algorithms.  See Knuth 4.5.2 if you care]

 */

long

gr_gcd (long m, long n)

{

  if (m < 0)

    m = -m;

  if (n < 0)

    n = -n;

  while (n != 0){

    long        t = m % n;

    m = n;

    n = t;

  }

  return m;

}

/*

 * These really need some configure hacking to figure out the right answer.

 * As a stop gap, try for a macro, and if not that, then try std::

 */

// returns a non-zero value if value is "not-a-number" (NaN), and 0 otherwise

#if defined(isnan) || !defined(CXX_HAS_STD_ISNAN)

int 

gr_isnan (double value)

{

  return isnan (value);

}

#else

int 

gr_isnan (double value)

{

  return std::isnan (value);

}

#endif

// returns a non-zero value if the value of x has its sign bit set.

//

// This  is  not  the  same  as `x < 0.0', because IEEE 754 floating point

// allows zero to be signed.  The comparison `-0.0 < 0.0'  is  false,  but

// `gr_signbit (-0.0)' will return a nonzero value.

#ifdef signbit

int 

gr_signbit (double x)

{

  return signbit (x);

}

#else

int 

gr_signbit (double x)

{

  return std::signbit (x);

}

#endif