# include <cmath>
# include <cstdlib>
# include <ctime>
# include <iomanip>
# include <iostream>

using namespace std;

# include "minimal_surface_exact.hpp"

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

//****************************************************************************80

int main ( )

//****************************************************************************80
//
//  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 ( );

  cout << "\n";
  cout << "minimal_surface_exact_test():\n";
  cout << "  C++ version.\n";
  cout << "  Test minimal_surface_exact().\n";

  srand48 ( seed );

  X = new double[n];
  X1 = new double[n];
  Y = new double[n];
  Y1 = new double[n];

  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.
//
  cout << "\n";
  cout << "  Linear solution residual at random points:\n";

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

  cout << "  RMS residual norm = " << r8vec_norm_rms ( n, R ) << "\n";

  delete [] R;
//
//  Helicoid solution.
//
  cout << "\n";
  cout << "  Helicoid solution residual at random points:\n";

  R = minimal_surface_helicoid_residual ( n, X, Y );

  cout << "  RMS residual norm = " << r8vec_norm_rms ( n, R ) << "\n";

  delete [] R;
//
//  Catenoid solution.
//
  cout << "\n";
  cout << "  Catenoid solution residual at random points:\n";

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

  cout << "  RMS residual norm = " << r8vec_norm_rms ( n, R ) << "\n";

  delete [] R;
//
//  Scherk solution.
//
  cout << "\n";
  cout << "  Scherk solution residual at random points:\n";

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

  cout << "  RMS residual norm = " << r8vec_norm_rms ( n, R ) << "\n";

  delete [] R;

  delete [] X;
  delete [] X1;
  delete [] Y;
  delete [] Y1;
//
//  Terminate.
//
  cout << "\n";
  cout << "minimal_surface_exact_test()\n";
  cout << "  Normal end of execution.\n";
  cout << "\n";
  timestamp ( );

  return 0;
}
//****************************************************************************80

double r8vec_norm_rms ( int n, double a[] )

//****************************************************************************80
//
//  Purpose:
//
//    r8vec_norm_rms() returns the RMS norm of an R8VEC.
//
//  Discussion:
//
//    An R8VEC is a vector of R8's.
//
//    The vector RMS norm is defined as:
//
//      R8VEC_RMS_NORM = 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.
//
//  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;
}
//****************************************************************************80

void timestamp ( )

//****************************************************************************80
//
//  Purpose:
//
//    timestamp() prints the current YMDHMS date as a time stamp.
//
//  Example:
//
//    31 May 2001 09:45:54 AM
//
//  Licensing:
//
//    This code is distributed under the MIT license. 
//
//  Modified:
//
//    19 March 2018
//
//  Author:
//
//    John Burkardt
//
{
# define TIME_SIZE 40

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

  now = std::time ( NULL );
  tm_ptr = std::localtime ( &now );

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

  std::cout << time_buffer << "\n";

  return;
# undef TIME_SIZE
}