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

# include "gaussian.h"

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

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

int main ( )

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

    gaussian_test() tests gaussian().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    09 July 2025

  Author:

    John Burkardt
*/
{
  timestamp ( );

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

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

  timestamp ( );

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

void gaussian_antideriv_test ( )

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

    gaussian_antideriv_test() tests gaussian_antideriv().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    09 July 2025

  Author:

    John Burkardt
*/
{
  double a;
  double b;
  char command_filename[255];
  FILE *command_unit;
  char data_filename[255];
  FILE *data_unit;
  char *header = "gaussian_antideriv";
  int i;
  double mu;
  int n;
  char png_filename[255];
  double sigma;
  double *x;
  double *y;

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

  mu = 0.0;
  sigma = 1.0;
  a = - 4.0;
  b = + 4.0;
  n = 101;
  x = r8vec_linspace_new ( n, a, b );
  y = ( double * ) malloc ( n * sizeof ( double ) );

  for ( i = 0; i < n; i++ )
  {
    y[i] = gaussian_antideriv ( mu, sigma, x[i] );
  }
/*
  Create a graphics data file.
*/
  strcpy ( data_filename, header );
  strcat ( data_filename, "_data.txt" );
  data_unit = fopen ( data_filename, "wt" );

  for ( i = 0; i < n; i++ )
  {
    fprintf ( data_unit, "%14.6g %14.6g\n", x[i], y[i] );
  }
  fclose ( data_unit );
  printf ( "\n" );
  printf ( "  Created graphics data file '%s'\n", data_filename );

  strcpy ( png_filename, header );
  strcat ( png_filename, ".png" );
/*
  Create graphics command file.
*/
  strcpy ( command_filename, header );
  strcat ( command_filename, "_commands.txt" );
  command_unit = fopen ( command_filename, "wt" );
  fprintf ( command_unit, "# %s\n", command_filename );
  fprintf ( command_unit, "#\n" );
  fprintf ( command_unit, "# Usage:\n" );
  fprintf ( command_unit, "#  gnuplot < %s\n", command_filename );
  fprintf ( command_unit, "#\n" );
  fprintf ( command_unit, "set term png\n" );
  fprintf ( command_unit, "set output '%s'\n", png_filename );
  fprintf ( command_unit, "set xlabel '<--- X --->'\n" );
  fprintf ( command_unit, "set ylabel '<-- Y(X) -->'\n" );
  fprintf ( command_unit, "set title 'antideriv(mu=0,sigma=1;x)'\n" );
  fprintf ( command_unit, "set grid\n" );
  fprintf ( command_unit, "set style data lines\n" );
  fprintf ( command_unit, 
    "plot '%s' using 1:2 lw 3 linecolor rgb 'blue'\n", data_filename );
  fclose ( command_unit );
  printf ( "  Created command file '%s'\n", command_filename );
/*
  Free memory.
*/
  free ( x );
  free ( y );

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

void gaussian_mu_test ( )

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

    gaussian_mu() varies the mu parameter.

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    09 July 2025

  Author:

    John Burkardt
*/
{
  double a;
  double b;
  char command_filename[255];
  FILE *command_unit;
  char data_filename[255];
  FILE *data_unit;
  char *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;
  char png_filename[255];
  double sigma;
  double *x;
  double *y;

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

  n_deriv = 0;
  sigma = 1.0;
  a = - 4.0;
  b = + 4.0;
  n = 101;
  x = r8vec_linspace_new ( n, a, b );
  y = ( double * ) malloc ( 5 * sizeof ( double ) );
/*
  Create a graphics data file.
*/
  strcpy ( data_filename, header );
  strcat ( data_filename, "_data.txt" );
  data_unit = fopen ( data_filename, "wt" );

  for ( i = 0; i < n; i++ )
  {
    fprintf ( data_unit, "  %14.6g", x[i] );
    for ( j = 0; j < 5; j++ )
    {
      y[j] = gaussian_value ( n_deriv, mu[j], sigma, x[i] );
      fprintf ( data_unit, "  %14.6g", y[j] );
    }
    fprintf ( data_unit, "\n" );
  }
  fclose ( data_unit );

  printf ( "\n" );
  printf ( "  Created graphics data file '%s'\n", data_filename );

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

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

void gaussian_n_test ( )

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

    gaussian_n_test() varies the n parameter.

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    09 July 2025

  Author:

    John Burkardt
*/
{
  double a;
  double b;
  char command_filename[255];
  FILE *command_unit;
  char data_filename[255];
  FILE *data_unit;
  int deriv;
  char header[80];
  int i;
  double mu;
  char png_filename[255];
  double sigma;
  int n = 101;
  double *x;
  double *y;

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

  mu = 0.0;
  sigma = 1.0;
  a = - 4.0;
  b = + 4.0;
  strcpy ( header, "gaussian_deriv_0" );
  x = r8vec_linspace_new ( n, a, b );
  y = ( double * ) malloc ( n * sizeof ( double ) );

  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.
*/
    strcpy ( data_filename, header );
    strcat ( data_filename, "_data.txt" );
    data_unit = fopen ( data_filename, "wt" );
    for ( i = 0; i < n; i++ )
    {
      fprintf ( data_unit, "%14.6g %14.6g\n", x[i], y[i] );
    }
    fclose ( data_unit );
    printf ( "\n" );
    printf ( "  Created graphics data file '%s'\n", data_filename );

    strcpy ( png_filename, header );
    strcat ( png_filename, ".png" );
/*
  Create graphics command file.
*/
    strcpy ( command_filename, header );
    strcat ( command_filename, "_commands.txt" );
    command_unit = fopen ( command_filename, "wt" );
    fprintf ( command_unit, "# %s\n", command_filename );
    fprintf ( command_unit, "#\n" );
    fprintf ( command_unit, "# Usage:\n" );
    fprintf ( command_unit, "#  gnuplot < %s\n", command_filename );
    fprintf ( command_unit, "#\n" );
    fprintf ( command_unit, "set term png\n" );
    fprintf ( command_unit, "set output '%s'\n", png_filename );
    fprintf ( command_unit, "set xlabel '<--- X --->'\n" );
    fprintf ( command_unit, "set ylabel '<-- Y(X) -->'\n" );
    fprintf ( command_unit, "set title '%s'\n", header );
    fprintf ( command_unit, "set grid\n" );
    fprintf ( command_unit, "set style data lines\n" );
    fprintf ( command_unit, 
      "plot '%s' using 1:2 lw 3 linecolor rgb 'blue'\n", data_filename );
    fclose ( command_unit );
    printf ( "  Created command file '%s'\n", command_filename );

    filename_inc ( header );
  }
/*
  Free memory.
*/
  free ( x );
  free ( y );

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

void gaussian_sigma_test ( )

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

    gaussian_sigma_test() varies the sigma parameter.

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    09 July 2025

  Author:

    John Burkardt
*/
{
  double a;
  double b;
  char command_filename[255];
  FILE *command_unit;
  char data_filename[255];
  FILE *data_unit;
  char *header = "gaussian_sigma";
  int i;
  int j;
  double mu;
  int n;
  int n_deriv;
  char png_filename[255];
  double sigma[5] = { 0.25, 0.50, 1.0, 1.5, 2.0 };
  double *x;
  double *y;

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

  n_deriv = 0;
  mu = 0.0;
  a = - 4.0;
  b = + 4.0;
  n = 101;
  x = r8vec_linspace_new ( n, a, b );
  y = ( double * ) malloc ( 5 * sizeof ( double ) );
/*
  Create a graphics data file.
*/
  strcpy ( data_filename, header );
  strcat ( data_filename, "_data.txt" );
  data_unit = fopen ( data_filename, "wt" );

  for ( i = 0; i < n; i++ )
  {
    fprintf ( data_unit, "  %14.6g", x[i] );
    for ( j = 0; j < 5; j++ )
    {
      y[j] = gaussian_value ( n_deriv, mu, sigma[j], x[i] );
      fprintf ( data_unit, "  %14.6g", y[j] );
    }
    fprintf ( data_unit, "\n" );
  }

  fclose ( data_unit );

  printf ( "\n" );
  printf ( "  Created graphics data file '%s'\n", data_filename );

  strcpy ( png_filename, header );
  strcat ( png_filename, ".png" );
/*
  Create graphics command file.
*/
  strcpy ( command_filename, header );
  strcat ( command_filename, "_commands.txt" );
  command_unit = fopen ( command_filename, "wt" );
  fprintf ( command_unit, "# %s\n", command_filename );
  fprintf ( command_unit, "#\n" );
  fprintf ( command_unit, "# Usage:\n" );
  fprintf ( command_unit, "#  gnuplot < %s\n", command_filename );
  fprintf ( command_unit, "#\n" );
  fprintf ( command_unit, "set term png\n" );
  fprintf ( command_unit, "set output '%s'\n", png_filename );
  fprintf ( command_unit, "set xlabel '<--- X --->'\n" );
  fprintf ( command_unit, "set ylabel '<-- Y(X) -->'\n" );
  fprintf ( command_unit, "set title 'g(mu,sigma=[0.25,0.50,1,1.5,2];x)'\n" );
  fprintf ( command_unit, "set grid\n" );
  fprintf ( command_unit, "set style data lines\n" );

  fprintf ( command_unit, 
    "plot '%s' using 1:2 lw 3 linecolor rgb 'blue',\\\n", data_filename );
  fprintf ( command_unit, 
    "     '%s' using 1:3 lw 3 linecolor rgb 'red',\\\n", data_filename );
  fprintf ( command_unit, 
    "     '%s' using 1:4 lw 3 linecolor rgb 'green',\\\n", data_filename );
  fprintf ( command_unit, 
    "     '%s' using 1:5 lw 3 linecolor rgb 'cyan',\\\n", data_filename );
  fprintf ( command_unit, 
    "     '%s' using 1:6 lw 3 linecolor rgb 'magenta',\n", data_filename );
  fclose ( command_unit );
  printf ( "  Created command file '%s'\n", command_filename );
/*
  Free memory.
*/
  free ( x );
  free ( y );

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

void filename_inc ( char *filename )

/******************************************************************************/
/*
  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:

    07 April 2014

  Author:

    John Burkardt

  Input:

    char *FILENAME, the filename to be incremented.

  Output:

    char *FILENAME, the incremented filename.
*/
{
  int change;
  int n;
  char *t;

  n = strlen ( filename );

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

  change = 0;

  t = filename + n - 1;
  
  while ( 0 < n )
  {
    if ( '0' <= *t && *t <= '9' )
    {
      change = change + 1;

      if ( *t == '9' )
      {
        *t = '0';
      }
      else
      {
        *t = *t + 1;
        return;
      }
    }
    t--;
    n--;
  }
/*
  No digits were found.  Return blank.
*/
  if ( change == 0 )
  {
    n = strlen ( filename );
    t = filename + n - 1;
    while ( 0 < n )
    {
      *t = ' ';
      t--;
      n--;
    }
  }

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

double *r8vec_linspace_new ( int n, double a, double b )

/******************************************************************************/
/*
  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, B, the first and last entries.

  Output:

    double R8VEC_LINSPACE_NEW[N], a vector of linearly spaced data.
*/
{
  int i;
  double *x;

  x = ( double * ) malloc ( n * sizeof ( double ) );

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

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
}