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

# include "minimal_surface_exact.h"

int main ( );
double r8vec_norm_rms ( int n, double a[] );
void timestamp ( );

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

int main ( )

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

    minimal_surface_exact_test() tests minimal_surface_exact().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    02 June 2025

  Author:

    John Burkardt
*/
{
  double a;
  double b;
  double c;
  int i;
  int n = 5;
  double *R;
  long long int seed = 123456789LL;
  double *X;
  double *X1;
  double *Y;
  double *Y1;

  timestamp ( );

  printf ( "\n" );
  printf ( "minimal_surface_exact_test():\n" );
  printf ( "  C version.\n" );
  printf ( "  Test minimal_surface_exact().\n" );

  srand48 ( seed );

  X = ( double * ) malloc ( n * sizeof ( double ) );
  X1 = ( double * ) malloc ( n * sizeof ( double ) );
  Y = ( double * ) malloc ( n * sizeof ( double ) );
  Y1 = ( double * ) malloc ( n * sizeof ( double ) );

  for ( i = 0; i < n; i++ )
  {
    X[i] = drand48 ( );
    X1[i] = X[i] + 1.0;
    Y[i] = drand48 ( );
    Y1[i] = Y[i] + 1.0;
  }
  a = 1.0;
  b = 2.0;
  c = 3.0;
/*
  Linear solution.
*/
  printf ( "\n" );
  printf ( "  Linear solution residual at random points:\n" );

  R = minimal_surface_linear_residual ( n, X, Y, a, b, c );

  printf ( "  RMS residual norm = %g\n", r8vec_norm_rms ( n, R ) );

  free ( R );
/*
  Helicoid solution.
*/
  printf ( "\n" );
  printf ( "  Helicoid solution residual at random points:\n" );

  R = minimal_surface_helicoid_residual ( n, X, Y );

  printf ( "  RMS residual norm = %g\n", r8vec_norm_rms ( n, R ) );

  free ( R );
/*
  Catenoid solution.
*/
  printf ( "\n" );
  printf ( "  Catenoid solution residual at random points:\n" );

  R = minimal_surface_catenoid_residual ( n, X1, Y1, a );

  printf ( "  RMS residual norm = %g\n", r8vec_norm_rms ( n, R ) );

  free ( R );
/*
  Scherk solution.
*/
  printf ( "\n" );
  printf ( "  Scherk solution residual at random points:\n" );

  R = minimal_surface_scherk_residual ( n, X, Y, a );

  printf ( "  RMS residual norm = %g\n", r8vec_norm_rms ( n, R ) );

  free ( R );

  free ( X );
  free ( X1 );
  free ( Y );
  free ( Y1 );
/*
  Terminate.
*/
  printf ( "\n" );
  printf ( "minimal_surface_exact_test()\n" );
  printf ( "  Normal end of execution.\n" );
  printf ( "\n" );
  timestamp ( );

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

double r8vec_norm_rms ( int n, double a[] )

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

    r8vec_norm_rms() returns the RMS norm of an R8VEC.

  Discussion:

    The vector RMS norm is defined as:

      R8VEC_NORM_RMS = sqrt ( sum ( 1 <= I <= N ) A(I)^2 / N )

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    26 October 2011

  Author:

    John Burkardt

  Input:

    int N, the number of entries in A.

    double A[N], the vector whose L2 norm is desired.

  Output:

    double R8VEC_NORM_RMS, the RMS norm of A.
*/
{
  int i;
  double v;

  v = 0.0;

  if ( 0 < n )
  {
    for ( i = 0; i < n; i++ )
    {
      v = v + a[i] * a[i];
    }
    v = sqrt ( v / ( double ) ( n ) );
  }

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

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
}