# include <math.h>
# include <stdlib.h>
# include <stdio.h>
# include <time.h>

# include "asa245.h"

int main ( );
void test01 ( );
void test02 ( );
void test03 ( );
void timestamp ( );

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

int main ( )

/******************************************************************************/
/*
  Purpose:

    asa245_test() tests asa245().

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    25 September 2014

  Author:

    John Burkardt
*/
{
  timestamp ( );
  printf ( "\n" );
  printf ( "asa245_test():\n" );
  printf ( "  C version\n" );
  printf ( "  Test asa245().\n" );

  test01 ( );
  test02 ( );
  test03 ( );
/*
  Terminate.
*/
  printf ( "\n" );
  printf ( "asa245_test():\n" );
  printf ( "  Normal end of execution.\n" );
  printf ( "\n" );
  timestamp ( );

  return 0;
}
/******************************************************************************/

void test01 ( )

/******************************************************************************/
/*
  Purpose:

    test01() tests alngam().

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    20 November 2010

  Author:

    John Burkardt
*/
{
  double fx;
  double fx2;
  int ifault;
  int n_data;
  double x;

  printf ( "\n" );
  printf ( "test01():\n" );
  printf ( "  alngam() computes the logarithm of the \n" );
  printf ( "  Gamma function.  We compare the result\n" );
  printf ( "  to tabulated values.\n" );
  printf ( "\n" );
  printf ( "          X                     " );
  printf ( "FX                        FX2\n" );
  printf ( "                                " );
  printf ( "(Tabulated)               (ALNGAM)                DIFF\n" );
  printf ( "\n" );

  n_data = 0;

  for ( ; ; )
  {
    gamma_log_values ( &n_data, &x, &fx );

    if ( n_data == 0 )
    {
      break;
    }

    fx2 = alngam ( x, &ifault );

    printf ( "  %24.16f  %24.16f  %24.16f  %10.4e\n",
      x, fx, fx2, fabs ( fx - fx2 ) );
  }

  return;
}
/******************************************************************************/

void test02 ( )

/******************************************************************************/
/*
  Purpose:

    test02() tests lngamma().

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    20 November 2010

  Author:

    John Burkardt
*/
{
  double fx;
  double fx2;
  int ier;
  int n_data;
  double x;

  printf ( "\n" );
  printf ( "test02():\n" );
  printf ( "  lngamma() computes the logarithm of the \n" );
  printf ( "  Gamma function.  We compare the result\n" );
  printf ( "  to tabulated values.\n" );
  printf ( "\n" );
  printf ( "          X                     " );
  printf ( "FX                        FX2\n" );
  printf ( "                                " );
  printf ( "(Tabulated)               (LNGAMMA)                DIFF\n" );
  printf ( "\n" );

  n_data = 0;

  for ( ; ; )
  {
    gamma_log_values ( &n_data, &x, &fx );

    if ( n_data == 0 )
    {
      break;
    }

    fx2 = lngamma ( x, &ier );

    printf ( "  %24.16f  %24.16f  %24.16f  %10.4e\n",
      x, fx, fx2, fabs ( fx - fx2 ) );
  }

  return;
}
/******************************************************************************/

void test03 ( )

/******************************************************************************/
/*
  Purpose:

    test03() tests lgamma().

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    25 September 2014

  Author:

    John Burkardt
*/
{
  double fx;
  double fx2;
  int n_data;
  double x;

  printf ( "\n" );
  printf ( "test03():\n" );
  printf ( "  lgamma() computes the logarithm of the \n" );
  printf ( "  Gamma function.\n" );
  printf ( "  LGAMMA is available with the GCC compiler.\n" );
  printf ( "  We compare the result to tabulated values.\n" );
  printf ( "\n" );
  printf ( "          X                     " );
  printf ( "FX                        FX2\n" );
  printf ( "                                " );
  printf ( "(Tabulated)               (LGAMMA)                 DIFF\n" );
  printf ( "\n" );

  n_data = 0;

  for ( ; ; )
  {
    gamma_log_values ( &n_data, &x, &fx );

    if ( n_data == 0 )
    {
      break;
    }

    fx2 = lgamma ( x );

    printf ( "  %24.16f  %24.16f  %24.16f  %10.4e\n",
      x, fx, fx2, fabs ( fx - fx2 ) );
  }

  return;
}
/******************************************************************************/

void timestamp ( )

/******************************************************************************/
/*
  Purpose:

    timestamp() prints the current YMDHMS date as a time stamp.

  Example:

    17 June 2014 09:45:54 AM

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    17 June 2014

  Author:

    John Burkardt
*/
{
# define TIME_SIZE 40

  static char time_buffer[TIME_SIZE];
  const struct tm *tm;
  time_t now;

  now = time ( NULL );
  tm = localtime ( &now );

  strftime ( time_buffer, TIME_SIZE, "%d %B %Y %I:%M:%S %p", tm );

  printf ( "%s\n", time_buffer );

  return;
# undef TIME_SIZE
}