// mappers.cc                                             -*- C++ -*-
/*

Copyright (C) 1992, 1993 John W. Eaton

This file is part of Octave.

Octave 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 2, or (at your option) any
later version.

Octave 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 Octave; see the file COPYING.  If not, write to the Free
Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#ifdef __GNUG__
#pragma implementation
#endif

#include <float.h>

#include "mappers.h"
#include "utils.h"

#if defined (_AIX) && defined (__GNUG__)
#undef finite
#define finite(x) ((x) < DBL_MAX && (x) > -DBL_MAX)
#endif

#ifndef M_LOG10E
#define M_LOG10E 0.43429448190325182765
#endif

#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif

/*
 * Double -> double mappers.
 */

double
arg (double x)
{
  if (x < 0.0)
    return M_PI;
  else
    return 0.0;
}

double
conj (double x)
{
  return x;
}

double
fix (double x)
{
  int tmp;
  tmp = (int) x;
  return (double) tmp;
}

double
imag (double x)
{
  return 0.0;
}

double
real (double x)
{
  return x;
}

double
round (double x)
{
  return D_NINT (x);
}

double
signum (double x)
{
  double tmp = 0.0;
  if (x < 0.0)
    tmp = -1.0;
  else if (x > 0.0)
    tmp = 1.0;
  return tmp;
}

double
xisnan (double x)
{
#if defined (HAVE_ISNAN)
  return (double) isnan (x);
#else
  return 0;
#endif
}

double
xfinite (double x)
{
#if defined (HAVE_FINITE)
  return (double) finite (x);
#elif defined (HAVE_ISINF) && defined (HAVE_ISNAN)
  return (double) (! isinf (x) && ! isnan (x));
#else
  return (double) (x > -DBL_MAX && x < DBL_MAX);
#endif
}

double
xisinf (double x)
{
#if defined (HAVE_ISINF)
  return (double) isinf (x);
#elif defined (HAVE_FINITE) && defined (HAVE_ISNAN)
  return (double) (! (finite (x) || isnan (x)));
#else
  return (double) (x == DBL_MAX || x == -DBL_MAX);
#endif
}

/*
 * Complex -> double mappers.
 */

double
xisnan (const Complex& x)
{
#if defined (HAVE_ISNAN)
  double rx = real (x);
  double ix = imag (x);
  return (double) (isnan (rx) || isnan (ix));
#else
  return 0;
#endif
}

double
xfinite (const Complex& x)
{
  double rx = real (x);
  double ix = imag (x);
  return (double) (! ((int) xisinf (rx) || (int) xisinf (ix)));
}

double
xisinf (const Complex& x)
{
  return (double) (! (int) xfinite (x));
}

/*
 * Complex -> complex mappers.
 */

Complex
acos (const Complex& x)
{
  static Complex i (0, 1);
  Complex retval = -i * log (x + sqrt (x*x - 1.0));
  return retval;
}

Complex
acosh (const Complex& x)
{
  Complex retval = log (x + sqrt (x*x - 1.0));
  return retval;
}

Complex
asin (const Complex& x)
{
  static Complex i (0, 1);
  Complex retval = -i * log (i*x + sqrt (1.0 - x*x));
  return retval;
}

Complex
asinh (const Complex& x)
{
  Complex retval = log (x + sqrt (x*x + 1.0));
  return retval;
}

Complex
atan (const Complex& x)
{
  static Complex i (0, 1);
  Complex retval = i * log ((i + x) / (i - x)) / 2.0;
  return retval;
}

Complex
atanh (const Complex& x)
{
  static Complex i (0, 1);
  Complex retval = log ((i + x) / (i - x)) / 2.0;
  return retval;
}

Complex
ceil (const Complex& x)
{
  int re = (int) ceil (real (x));
  int im = (int) ceil (imag (x));
  return Complex (re, im);
}

Complex
fix (const Complex& x)
{
  int re = (int) real (x);
  int im = (int) imag (x);
  return Complex (re, im);
}

Complex
floor (const Complex& x)
{
  int re = (int) floor (real (x));
  int im = (int) floor (imag (x));
  return Complex (re, im);
}

Complex
log10 (const Complex& x)
{
  return M_LOG10E * log (x);
}

Complex
round (const Complex& x)
{
  double re = D_NINT (real (x));
  double im = D_NINT (imag (x));
  return Complex (re, im);
}

Complex
signum (const Complex& x)
{
  return x / abs (x);
}

Complex
tan (const Complex& x)
{
  Complex retval = sin (x) / cos (x);
  return retval;
}

Complex
tanh (const Complex& x)
{
  Complex retval = sinh (x) / cosh (x);
  return retval;
}

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