#! /usr/bin/env python3
#
def humps_plot ( ):

#*****************************************************************************80
#
## humps_plot() plots y=humps(x) directly from the formula.
#
#  Licensing:
#
#    This code is distributed under the MIT license.
#
#  Modified:
#
#    27 September 2026
#
#  Author:
#
#    John Burkardt
#
  import matplotlib
  import numpy as np
  import platform

  print ( '' )
  print ( 'humps_plot():' )
  print ( '  matplotlib version: ' + matplotlib.__version__ )
  print ( '  numpy version:      ' + np.version.version )
  print ( '  python version:     ' + platform.python_version ( ) )
  print ( '  Plot y=humps(x) directly from the formula.' )

  header = 'humps'
#
#  Create the command file.
#
  command_filename = header + '_commands.txt'
  command_unit = open ( command_filename, 'wt' )
  command_unit.write ( '# ' + command_filename + '\n' )
  command_unit.write ( '#\n' )
  command_unit.write ( '# Usage:\n' )
  command_unit.write ( '#  gnuplot < ' + command_filename + '\n' )
  command_unit.write ( '#\n' )
  command_unit.write ( 'set term png\n' )
  command_unit.write ( 'set output "' + header + '.png"\n' )
  command_unit.write ( 'set xlabel "x"\n' )
  command_unit.write ( 'set ylabel "y"\n' )
  command_unit.write ( 'set title "y = humps(x)"\n' )
  command_unit.write ( 'set grid\n' )
  command_unit.write ( 'set timestamp\n' )
  command_unit.write ( 'set style data lines\n' )
  command_unit.write ( 'set xrange [0.0:2.0]\n' )
  command_unit.write ( 'set samples 51\n' )
  command_unit.write ( 'f(x)=1.0/((x-0.3)**2+0.01)+1.0/((x-0.9)**2+0.04)-6.0\n' )
  command_unit.write ( 'plot f(x) with linespoints pt 7 ps 2\n' )
  command_unit.write ( 'quit\n' )
  command_unit.close ( )
  print ( '  Created command file "' + command_filename + '"' )

  return

def timestamp ( ):

#*****************************************************************************80
#
## timestamp() prints the date as a timestamp.
#
#  Licensing:
#
#    This code is distributed under the MIT license. 
#
#  Modified:
#
#    21 August 2019
#
#  Author:
#
#    John Burkardt
#
  import time

  t = time.time ( )
  print ( time.ctime ( t ) )

  return

if ( __name__ == '__main__' ):
  timestamp ( )
  humps_plot ( )
  timestamp ( )