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

# include "dislin.h"

int main ( int argc, char *argv[] );
void timestamp ( );

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

int main ( int argc, char *argv[] )

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

    humps_plot_dislin() makes a line plot of y=humps(x).

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    28 September 2024

  Author:

    John Burkardt

  Reference:

    Helmut Michels,
    The Data Plotting Software DISLIN - version 10.4,
    Shaker Media GmbH, January 2010,
    ISBN13: 978-3-86858-517-9.
*/
{
  char *filename_plot = "humps_plot_dislin.png";
  int i;
  int m;
  float *x;
  float xmax;
  float xmin;
  float xstep;
  float *y;
  float ymax;
  float ymin;
  float ystep;

  timestamp ( );
  printf ( "\n" );
  printf ( "humps_plot_dislin():\n" );
  printf ( "  C version:\n" );
  printf ( "  dislin() plots y=humps(x).\n" );
/*
  Set M, the number of data pairs.
*/
  m = 101;
/*
  Set the X, Y data.
*/
  xmin = 0.0;
  xmax = 2.0;

  x = ( float * ) malloc ( m * sizeof ( float ) );
  y = ( float * ) malloc ( m * sizeof ( float ) );
  ymin =   DBL_MAX;
  ymax = - DBL_MAX;
  for ( i = 0; i < m; i++ )
  {
    x[i] = ( ( m - 1 - i ) * xmin + ( i ) * xmax ) / ( m - 1 );
    y[i] = 1.0 / ( pow ( x[i] - 0.3, 2 ) + 0.01 )
         + 1.0 / ( pow ( x[i] - 0.9, 2 ) + 0.04 ) - 6.0;
    ymin = fmin ( ymin, y[i] );
    ymax = fmax ( ymax, y[i] );
  }
/*
  Specify the format of the output file.
*/
  metafl ( "png" );
/*
  Indicate that new data overwrites old data.
*/
  filmod ( "delete" );
/*
  Specify the name of the output graphics file.
*/
  setfil ( filename_plot );
/*
  Choose the page size and orientation.
  'USA' is 2160 plot units wide and 2790 plot units high.
  'L' requests LANDSCAPE orientation.
*/
  setpag ( "usal" );
/*
  For PNG output, reverse the default black background to white.
*/
  scrmod ( "reverse" );
/*
  Open DISLIN.
*/
  disini ( );
/*
  Plot a border around the page.
*/
  pagera ( );
/*
  Use the SIMPLX font.
*/
  simplx ( );
/*
  Set the axis origin 500 plot units to the right, and 1900 plot units DOWN.
*/
  axspos ( 500, 1900 );
/*
  Define the X and Y sizes of the axis system in plot units.
*/
  axslen ( 2190, 1260 );
/*
  Label the X and Y axes.
*/
  name ( "x", "X" );
  name ( "y=humps(x)", "Y" );
/*
  Don't use any digits after the decimal points on X and Y tick marks.
*/
  labdig ( -1, "X" );
  labdig ( -1, "Y" );
/*
  Relate the physical coordinates to the axes, and specify tick marks.
*/
  xstep = ( xmax - xmin ) / 10;
  ystep = ( ymax - ymin ) / 10;

  graf ( xmin, xmax, xmin, xstep, ymin, ymax, ymin, ystep );
/*
  BEGIN LEVEL 2 COMMANDS.
*/

/*
  Define the title.
*/
  titlin ( "y=humps(x)", 1 );
  title ( );
/*
  Add a grid, with one grid line for every tick mark in the X and Y axes.
*/
  grid ( 1, 1 );
/*
  Set the drawing color to "blue";
*/
  color ( "blue" );
/*
  Specify linewidth.
*/
  linwid ( 15 );
/*
  Draw the curve.
*/
  curve ( x, y, m );
/*
  End this graph.
*/
  endgrf ( );
/*
  RETURN FROM LEVEL 2 TO LEVEL 1.
*/
  printf ( "  Graphics saved as '%s'\n", filename_plot );
/*
  Close DISLIN.
*/
  disfin ( );
/*
  Free memory.
*/
  free ( x );
  free ( y );
/*
  Terminate.
*/
  printf ( "\n" );
  printf ( "humps_plot_dislin():\n" );
  printf ( "  Normal end of execution.\n" );
  printf ( "\n" );
  timestamp ( );

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

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:

    17 June 2014

  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
}