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

# include "ellipse.h"

int main ( );
void ellipse_area1_test ( );
void ellipse_area2_test ( );
void ellipse_area3_test ( );
void ellipse_aspect_ratio_test ( );
void ellipse_eccentricity_test ( );
void ellipse_flattening_test ( );
void timestamp ( );

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

int main ( )

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

    ellipse_test() tests ellipse().

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    14 October 2022

  Author:

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

  ellipse_area1_test ( );
  ellipse_area2_test ( );
  ellipse_area3_test ( );
  ellipse_aspect_ratio_test ( );
  ellipse_eccentricity_test ( );
  ellipse_flattening_test ( );
/*
  Terminate.
*/
  printf ( "\n" );
  printf ( "ellipse_test():\n" );
  printf ( "  Normal end of execution.\n" );
  printf ( "\n" );
  timestamp ( );

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

void ellipse_area1_test ( )

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

    ellipse_area1_test() tests ellipse_area1().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    07 April 2022

  Author:

    John Burkardt
*/
{
  double a[2*2] = { 5.0, 1.0, 1.0, 2.0 };
  double area;
  double r;

  printf ( "\n" );
  printf ( "ellipse_area1_test():\n" );
  printf ( "  ellipse_area1() computes the area of an ellipse.\n" );

  r = 10.0;

  area = ellipse_area1 ( a, r );

  printf ( "\n" );
  printf ( "  R = %g\n", r );
  printf ( "\n" );
  printf ( "  Matrix A in ellipse definition x*A*x=r^2:\n" );
  printf ( "    [ %g  %g ]\n", a[0+0*2], a[0+1*2] );
  printf ( "    [ %g  %g ]\n", a[1+1*2], a[1+1*2] );
  printf ( "  Area = %g\n", area );

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

void ellipse_area2_test ( )

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

    ellipse_area2_test() tests ellipse_area2().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    08 November 2016

  Author:

    John Burkardt
*/
{
  double a;
  double area;
  double b;
  double c;
  double d;
 
  printf ( "\n" );
  printf ( "ellipse_area2_test():\n" );
  printf ( "  ellipse_area2() computes the area of an ellipse.\n" );

  a = 5.0;
  b = 2.0;
  c = 2.0;
  d = 10.0;

  area = ellipse_area2 ( a, b, c, d );

  printf ( "\n" );
  printf ( "  Ellipse: %g * x^2 + %g * xy + %g * y^2 = %g\n", a, b, c, d );
  printf ( "  Area = %g\n", area );

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

void ellipse_area3_test ( )

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

    ellipse_area3_test() tests ellipse_area3().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    08 November 2016

  Author:

    John Burkardt
*/
{
  double area;
  double r1;
  double r2;
 
  printf ( "\n" );
  printf ( "ellipse_area3_test():\n" );
  printf ( "  ellipse_area3() computes the area of an ellipse.\n" );

  r1 = 10.0;
  r2 = 10.0 / 3.0;

  area = ellipse_area3 ( r1, r2 );

  printf ( "\n" );
  printf ( "  Ellipse: (x/%g)^2 + (y/%g)^2 = 1\n", r1, r2 );
  printf ( "  Area = %g\n", area );

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

void ellipse_aspect_ratio_test ( )

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

    ellipse_aspect_ratio_test() tests ellipse_aspect_ratio().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    14 October 2022

  Author:

    John Burkardt
*/
{
  double a;
  double b;
  double e;
  int i;
  int n;
 
  printf ( "\n" );
  printf ( "ellipse_aspect_ratio_test():\n" );
  printf ( "  ellipse_aspect_ratio() computes the aspect ratio of an ellipse.\n" );

  printf ( "\n" );
  printf ( "      A      B      Ratio\n" );
  printf ( "\n" );
  a = 1.0;
  n = 10;
  for ( i = 0; i <= n; i++ )
  {
    b = ( double ) ( i ) / ( double ) ( n );
    e = ellipse_aspect_ratio ( a, b );
    printf ( "  %5.1f  %5.1f  %10.6f\n", a, b, e );
  }

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

void ellipse_eccentricity_test ( )

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

    ellipse_eccentricity_test() tests ellipse_eccentricity().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    24 March 2021

  Author:

    John Burkardt
*/
{
  double a;
  double b;
  double e;
  int i;
  int n;
 
  printf ( "\n" );
  printf ( "ellipse_eccentricity_test():\n" );
  printf ( "  ellipse_eccentricity() computes the eccentricity of an ellipse.\n" );

  printf ( "\n" );
  printf ( "      A      B      Ecc\n" );
  printf ( "\n" );
  a = 1.0;
  n = 10;
  for ( i = 0; i <= n; i++ )
  {
    b = ( double ) ( i ) / ( double ) ( n );
    e = ellipse_eccentricity ( a, b );
    printf ( "  %5.1f  %5.1f  %10.6f\n", a, b, e );
  }

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

void ellipse_flattening_test ( )

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

    ellipse_flattening_test() tests ellipse_flattening().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    14 October 2022

  Author:

    John Burkardt
*/
{
  double a;
  double b;
  double e;
  int i;
  int n;
 
  printf ( "\n" );
  printf ( "ellipse_flattening_test():\n" );
  printf ( "  ellipse_flattening() computes the flattening of an ellipse.\n" );

  printf ( "\n" );
  printf ( "      A      B      Flat\n" );
  printf ( "\n" );
  a = 1.0;
  n = 10;
  for ( i = 0; i <= n; i++ )
  {
    b = ( double ) ( i ) / ( double ) ( n );
    e = ellipse_flattening ( a, b );
    printf ( "  %5.1f  %5.1f  %10.6f\n", a, b, e );
  }

  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:

    01 May 2021

  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
}