# include <cstdlib>
# include <cstring>
# include <ctime>
# include <fstream>
# include <iomanip>
# include <iostream>

using namespace std;

# include "gaussian.hpp"

int main ( );
void gaussian_antideriv_test ( );
void gaussian_n_test ( );
void gaussian_mu_test ( );
void gaussian_sigma_test ( );
void filename_inc ( string *filename );
double *r8vec_linspace_new ( int n, double a, double b );
void timestamp ( );

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

int main ( )

//****************************************************************************80
//
//  Purpose:
//
//    gaussian_test() tests gaussian().
//
//  Licensing:
//
//    This code is distributed under the MIT license.
//
//  Modified:
//
//    10 July 2025
//
//  Author:
//
//    John Burkardt
//
{
  timestamp ( );

  cout << "\n";
  cout << "gaussian_test():\n";
  cout << "  C++ version\n";
  cout << "  gaussian() evaluates a Gaussian function,\n";
  cout << "  its antiderivative, or derivatives of any order.\n";

  gaussian_antideriv_test ( );
  gaussian_n_test ( );
  gaussian_mu_test ( );
  gaussian_sigma_test ( );
//
//  Terminate.
//
  cout << "\n";
  cout << "gaussian_test()\n";
  cout << "  Normal end of execution.\n";

  timestamp ( );

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

void gaussian_antideriv_test ( )

//****************************************************************************80
//
//  Purpose:
//
//    gaussian_antideriv_test() tests gaussian_antideriv().
//
//  Licensing:
//
//    This code is distributed under the MIT license.
//
//  Modified:
//
//    10 July 2025
//
//  Author:
//
//    John Burkardt
//
{
  double a;
  double b;
  string command_filename;
  ofstream command_unit;
  string data_filename;
  ofstream data_unit;
  string header = "gaussian_antideriv";
  int i;
  double mu;
  int n;
  string png_filename;
  double sigma;
  double *x;
  double *y;

  cout << "\n";
  cout << "gaussian_antideriv_test():\n";
  cout << "  Compute gaussian_antideriv(mu=0,sigma=1;x).\n";
  cout << "\n";

  mu = 0.0;
  sigma = 1.0;
  a = - 4.0;
  b = + 4.0;
  n = 101;
  x = r8vec_linspace_new ( n, a, b );
  y = new double[n];

  for ( i = 0; i < n; i++ )
  {
    y[i] = gaussian_antideriv ( mu, sigma, x[i] );
  }
//
//  Create a graphics data file.
//
  data_filename = header +"_data.txt";
  data_unit.open ( data_filename.c_str ( ) );
  for ( i = 0; i < n; i++ )
  {
    data_unit << x[i] << "  "
              << y[i] << "\n";
  }
  data_unit.close ( );
  cout << "\n";
  cout << "  Created graphics data file '" << data_filename << "'\n";

  png_filename = header + ".png";
//
//  Create graphics command file.
//
  command_filename = header + "_commands.txt";
  command_unit.open ( command_filename.c_str() );
  command_unit << "# " << command_filename << "\n";
  command_unit << "#\n";
  command_unit << "# Usage:\n";
  command_unit << "#  gnuplot < " << command_filename << "\n";
  command_unit << "#\n";
  command_unit << "set term png\n";
  command_unit << "set output '" << png_filename << "'\n";
  command_unit << "set xlabel '<--- X --->'\n";
  command_unit << "set ylabel '<-- Y(X) -->'\n";
  command_unit << "set title 'antideriv(mu=0,sigma=1;x)'\n";
  command_unit << "set grid\n";
  command_unit << "set style data lines\n";
  command_unit << 
    "plot '" << data_filename << "' using 1:2 lw 3 linecolor rgb 'blue'\n";
  command_unit.close ( );
  cout << "  Created command file '" << command_filename << "'\n";
//
//  Free memory.
//
  delete [] x;
  delete [] y;

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

void gaussian_mu_test ( )

//****************************************************************************80
//
//  Purpose:
//
//    gaussian_mu() varies the mu parameter.
//
//  Licensing:
//
//    This code is distributed under the MIT license.
//
//  Modified:
//
//    10 July 2025
//
//  Author:
//
//    John Burkardt
//
{
  double a;
  double b;
  string command_filename;
  ofstream command_unit;
  string data_filename;
  ofstream data_unit;
  string header = "gaussian_mu";
  int i;
  int j;
  double mu[5] = { -1.0, -0.5, 0.0, 0.5, 1.0 };
  int n;
  int n_deriv;
  string png_filename;
  double sigma;
  double *x;
  double *y;

  cout << "\n";
  cout << "gaussian_sigma_test():\n";
  cout << "  Compute gaussian(n,mu,sigma;x) for various values of mu.\n";
  cout << "\n";

  n_deriv = 0;
  sigma = 1.0;
  a = - 4.0;
  b = + 4.0;
  n = 101;
  x = r8vec_linspace_new ( n, a, b );
  y = new double[5];
//
//  Create a graphics data file.
//
  data_filename = header +"_data.txt";
  data_unit.open ( data_filename.c_str ( ) );

  for ( i = 0; i < n; i++ )
  {
    data_unit << x[i];
    for ( j = 0; j < 5; j++ )
    {
      y[j] = gaussian_value ( n_deriv, mu[j], sigma, x[i] );
      data_unit << "  " << y[j];
    }
    data_unit << "\n";
  }
  data_unit.close ( );

  cout << "\n";
  cout << "  Created graphics data file '" << data_filename << "'\n";

  png_filename = header + ".png";
//
//  Create graphics command file.
//
  command_filename = header + "_commands.txt";
  command_unit.open ( command_filename.c_str() );
  command_unit << "# " << command_filename << "\n";
  command_unit << "#\n";
  command_unit << "# Usage:\n";
  command_unit << "#  gnuplot < " << command_filename << "\n";
  command_unit << "#\n";
  command_unit << "set term png\n";
  command_unit << "set output '" << png_filename << "'\n";
  command_unit << "set xlabel '<--- X --->'\n";
  command_unit << "set ylabel '<-- Y(X) -->'\n";
  command_unit << "set title 'g(mu=[-1,-1/2,0,1/2,1],sigma;x)'\n";
  command_unit << "set grid\n";
  command_unit << "set style data lines\n";
  command_unit << 
    "plot '" << data_filename << "' using 1:2 lw 3 linecolor rgb 'blue',\\\n";
  command_unit << 
    "     '" << data_filename << "' using 1:3 lw 3 linecolor rgb 'red',\\\n";
  command_unit << 
    "     '" << data_filename << "' using 1:4 lw 3 linecolor rgb 'green',\\\n";
  command_unit << 
    "     '" << data_filename << "' using 1:5 lw 3 linecolor rgb 'cyan',\\\n";
  command_unit << 
    "     '" << data_filename << "' using 1:6 lw 3 linecolor rgb 'magenta',\n";
  command_unit.close ( );
  cout << "  Created command file '" << command_filename << "'\n";
//
//  Free memory.
//
  delete [] x;
  delete [] y;

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

void gaussian_n_test ( )

//****************************************************************************80
//
//  Purpose:
//
//    gaussian_n_test() varies the n parameter.
//
//  Licensing:
//
//    This code is distributed under the MIT license.
//
//  Modified:
//
//    10 July 2025
//
//  Author:
//
//    John Burkardt
//
{
  double a;
  double b;
  string command_filename;
  ofstream command_unit;
  string data_filename;
  ofstream data_unit;
  int deriv;
  string header;
  int i;
  double mu;
  string png_filename;
  double sigma;
  int n = 101;
  double *x;
  double *y;

  cout << "\n";
  cout << "gaussian_n_test():\n";
  cout << "  gaussian(n,mu,sigma;x) evaluates the nth derivative.\n";
  cout << "\n";

  mu = 0.0;
  sigma = 1.0;
  a = - 4.0;
  b = + 4.0;
  header = "gaussian_deriv_0";
  x = r8vec_linspace_new ( n, a, b );
  y = new double[n];

  for ( deriv = 0; deriv <= 5; deriv++ )
  {
    for ( i = 0; i < n; i++ )
    {
      y[i] = gaussian_value ( deriv, mu, sigma, x[i] );
    }
//
//  Create a graphics data file.
//
    data_filename = header +"_data.txt";
    data_unit.open ( data_filename.c_str ( ) );
    for ( i = 0; i < n; i++ )
    {
      data_unit << x[i] << "  "
                << y[i] << "\n";
    }
    data_unit.close ( );
    cout << "\n";
    cout << "  Created graphics data file '" << data_filename << "'\n";

    png_filename = header + ".png";
//
//  Create graphics command file.
//
    command_filename = header + "_commands.txt";
    command_unit.open ( command_filename.c_str() );
    command_unit << "# " << command_filename << "\n";
    command_unit << "#\n";
    command_unit << "# Usage:\n";
    command_unit << "#  gnuplot < " << command_filename << "\n";
    command_unit << "#\n";
    command_unit << "set term png\n";
    command_unit << "set output '" << png_filename << "'\n";
    command_unit << "set xlabel '<--- X --->'\n";
    command_unit << "set ylabel '<-- Y(X) -->'\n";
    command_unit << "set title '" << header << "'\n";
    command_unit << "set grid\n";
    command_unit << "set style data lines\n";
    command_unit << 
      "plot '" << data_filename << "' using 1:2 lw 3 linecolor rgb 'blue'\n";
    command_unit.close ( );
    cout << "  Created command file '" << command_filename << "'\n";

    filename_inc ( &header );
  }
//
//  Free memory.
//
  delete [] x;
  delete [] y;

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

void gaussian_sigma_test ( )

//****************************************************************************80
//
//  Purpose:
//
//    gaussian_sigma_test() varies the sigma parameter.
//
//  Licensing:
//
//    This code is distributed under the MIT license.
//
//  Modified:
//
//    10 July 2025
//
//  Author:
//
//    John Burkardt
//
{
  double a;
  double b;
  string command_filename;
  ofstream command_unit;
  string data_filename;
  ofstream data_unit;
  string header = "gaussian_sigma";
  int i;
  int j;
  double mu;
  int n;
  int n_deriv;
  string png_filename;
  double sigma[5] = { 0.25, 0.50, 1.0, 1.5, 2.0 };
  double *x;
  double *y;

  cout << "\n";
  cout << "gaussian_sigma_test():\n";
  cout << "  Compute gaussian(n,mu,sigma,x) for various values of sigma.\n";
  cout << "\n";

  n_deriv = 0;
  mu = 0.0;
  a = - 4.0;
  b = + 4.0;
  n = 101;
  x = r8vec_linspace_new ( n, a, b );
  y = new double[5];
//
//  Create a graphics data file.
//
  data_filename = header + "_data.txt";
  data_unit.open ( data_filename.c_str ( ) );

  for ( i = 0; i < n; i++ )
  {
    data_unit << x[i];
    for ( j = 0; j < 5; j++ )
    {
      y[j] = gaussian_value ( n_deriv, mu, sigma[j], x[i] );
      data_unit << "  " << y[j];
    }
    data_unit << "\n";
  }

  data_unit.close ( );

  cout << "\n";
  cout << "  Created graphics data file '" << data_filename << "'\n";

  png_filename = header + ".png";
//
//  Create graphics command file.
//
  command_filename = header + "_commands.txt";
  command_unit.open ( command_filename.c_str() );
  command_unit << "# " << command_filename << "\n";
  command_unit << "#\n";
  command_unit << "# Usage:\n";
  command_unit << "#  gnuplot < " << command_filename << "\n";
  command_unit << "#\n";
  command_unit << "set term png\n";
  command_unit << "set output '" << png_filename << "'\n";
  command_unit << "set xlabel '<--- X --->'\n";
  command_unit << "set ylabel '<-- Y(X) -->'\n";
  command_unit << "set title 'g(mu,sigma=[0.25,0.50,1,1.5,2];x)'\n";
  command_unit << "set grid\n";
  command_unit << "set style data lines\n";
  command_unit << 
    "plot '" << data_filename << "' using 1:2 lw 3 linecolor rgb 'blue',\\\n";
  command_unit << 
    "     '" << data_filename << "' using 1:3 lw 3 linecolor rgb 'red',\\\n";
  command_unit << 
    "     '" << data_filename << "' using 1:4 lw 3 linecolor rgb 'green',\\\n";
  command_unit << 
    "     '" << data_filename << "' using 1:5 lw 3 linecolor rgb 'cyan',\\\n";
  command_unit << 
    "     '" << data_filename << "' using 1:6 lw 3 linecolor rgb 'magenta',\n";
  command_unit.close ( );
  cout << "  Created command file '" << command_filename << "'\n";
//
//  Free memory.
//
  delete [] x;
  delete [] y;

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

void filename_inc ( string *filename )

//****************************************************************************80
//
//  Purpose:
//
//    filename_inc() increments a partially numeric file name.
//
//  Discussion:
//
//    It is assumed that the digits in the name, whether scattered or
//    connected, represent a number that is to be increased by 1 on
//    each call.  If this number is all 9's on input, the output number
//    is all 0's.  Non-numeric letters of the name are unaffected.
//
//    If the name is empty, then the routine stops.
//
//    If the name contains no digits, the empty string is returned.
//
//  Example:
//
//      Input            Output
//      -----            ------
//      "a7to11.txt"     "a7to12.txt"  (typical case.  Last digit incremented)
//      "a7to99.txt"     "a8to00.txt"  (last digit incremented, with carry.)
//      "a9to99.txt"     "a0to00.txt"  (wrap around)
//      "cat.txt"        " "           (no digits to increment)
//      " "              STOP!         (error)
//
//  Licensing:
//
//    This code is distributed under the MIT license. 
//
//  Modified:
//
//    22 November 2011
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input/output, string *FILENAME, the filename to be incremented.
//
{
  char c;
  int change;
  int i;
  int lens;

  lens = (*filename).length ( );

  if ( lens <= 0 )
  {
    cerr << "\n";
    cerr << "filename_inc(): Fatal error!\n";
    cerr << "  The input string is empty.\n";
    exit ( 1 );
  }

  change = 0;

  for ( i = lens - 1; 0 <= i; i-- )
  {
    c = (*filename)[i];

    if ( '0' <= c && c <= '9' )
    {
      change = change + 1;

      if ( c == '9' )
      {
        c = '0';
        (*filename)[i] = c;
      }
      else
      {
        c = c + 1;
        (*filename)[i] = c;
        return;
      }
    }
  }
//
//  No digits were found.  Return blank.
//
  if ( change == 0 )
  {
    for ( i = lens - 1; 0 <= i; i-- )
    {
      (*filename)[i] = ' ';
    }
  }

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

double *r8vec_linspace_new ( int n, double a_first, double a_last )

//****************************************************************************80
//
//  Purpose:
//
//    r8vec_linspace_new() creates a vector of linearly spaced values.
//
//  Discussion:
//
//    An R8VEC is a vector of R8's.
//
//    4 points evenly spaced between 0 and 12 will yield 0, 4, 8, 12.
//
//    In other words, the interval is divided into N-1 even subintervals,
//    and the endpoints of intervals are used as the points.
//
//  Licensing:
//
//    This code is distributed under the MIT license.
//
//  Modified:
//
//    29 March 2011
//
//  Author:
//
//    John Burkardt
//
//  Input:
//
//    int N, the number of entries in the vector.
//
//    double A_FIRST, A_LAST, the first and last entries.
//
//  Output:
//
//    double R8VEC_LINSPACE_NEW[N], a vector of linearly spaced data.
//
{
  double *a;
  int i;

  a = new double[n];

  if ( n == 1 )
  {
    a[0] = ( a_first + a_last ) / 2.0;
  }
  else
  {
    for ( i = 0; i < n; i++ )
    {
      a[i] = ( ( double ) ( n - 1 - i ) * a_first 
             + ( double ) (         i ) * a_last ) 
             / ( double ) ( n - 1     );
    }
  }
  return a;
}
//****************************************************************************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
}