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

#*****************************************************************************80
#
## forge_classify_svm() uses the support vector classifier on forge data.
#
#  Licensing:
#
#    This code is distributed under the MIT license.
#
#  Modified:
#
#    04 July 2023
#
#  Author:
#
#    Andreas Mueller, Sarah Guido.
#    Modifications by John Burkardt.
#
#  Reference:
#
#    Andreas Mueller, Sarah Guido,
#    Introduction to Machine Learning with Python,
#    OReilly, 2017,
#    ISBN: 978-1-449-36941-5
#
  from sklearn.svm import LinearSVC
  import matplotlib.pyplot as plt
  import mglearn
  import numpy as np
  import pandas as pd
  import platform
  import sklearn

  print ( '' )
  print ( 'forge_classify_svm():' )
  print ( '  Python version: ' + platform.python_version ( ) )
  print ( '  scikit-learn version: '+ sklearn.__version__ )
  print ( '  Classify the data from the forge dataset.' )
  print ( '  Use the support vector classifier.' )
  print ( '  Vary the C parameter.' )
  print ( '' )
#
#  Generate the dataset.
#
  print ( '  Generate the forge dataset, (X, y).' )
  X, y = mglearn.datasets.make_forge ( )

  print ( "  X.shape:", X.shape )

  for c_value in [ 0.01, 10.0, 1000.0 ]:

    clf = LinearSVC ( C = c_value ).fit ( X, y )
    mglearn.plots.plot_2d_separator ( clf, X, fill = False, eps = 0.5, alpha = 0.7 )
    mglearn.discrete_scatter ( X[:,0], X[:,1], y )
    plt.title ( 'C = ' + str ( c_value ) )
    plt.xlabel ( 'Feature 0' )
    plt.ylabel ( 'Feature 1' )
    plt.legend()
    filename = "forge_classify_" + str ( c_value ) + ".png"
    plt.savefig ( filename )
    print ( "  Graphics saved as '" + filename + "'" )
    plt.close ( )
#
#  Terminate.
#
  print ( '' )
  print ( 'forge_classify_svm():' )
  print ( '  Normal end of execution.' )

  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 ( )
  forge_classify_svm ( )
  timestamp ( )