#! /usr/bin/env python3
#
def python03 ( ):

  import matplotlib.pyplot as plt
  import numpy as np

  n = 11
  x = np.linspace ( -2.0, 2.0, n )
  y = x**2 + np.sin ( 53.0 * x )
  plt.plot ( x, y )
  filename = 'plot01.png'
  plt.show ( block = False )
  plt.savefig ( filename )
  print ( '  Graphics saved as "' + filename + '"' )
  plt.close ( )
#
#  Try again, with more points.  Also, display the points with 'o'
#
  n = 21
  x = np.linspace ( -2.0, 2.0, n )  # because n changed, we have to recompute x
  y = x**2 + np.sin ( 53.0 * x )    # and then y
  plt.plot ( x, y, '-o' )
  filename = 'plot02.png'
  plt.show ( block = False )
  plt.savefig ( filename )
  print ( '  Graphics saved as "' + filename + '"' )
  plt.close ( )
#
#  Again, but no connecting lines.
#
  n = 101
  x = np.linspace ( -2.0, 2.0, n )
  y = x**2 + np.sin ( 53.0 * x )
  plt.plot ( x, y, '.' )
  plt.xlabel ( '<--- X axis --->' )
  plt.ylabel ( '<--- Y = F(X) --->' )
  filename = 'plot03.png'
  plt.show ( block = False )
  plt.savefig ( filename )
  print ( '  Graphics saved as "' + filename + '"' )
  plt.close ( )
#
#  OK, 1001 points has got to be enough!
#
  n = 1001
  x = np.linspace ( -2.0, 2.0, n )
  y = x**2 + np.sin ( 53.0 * x )
  plt.plot ( x, y, '-' )
  plt.grid ( True )
  plt.title ( '1001 data points' )
  filename = 'plot04.png'
  plt.show ( block = False )
  plt.savefig ( filename )
  print ( '  Graphics saved as "' + filename + '"' )
  plt.close ( )
#
#  Two curves on one plot.
#
  n = 101
  x = np.linspace ( 0.0, 2.0 * np.pi, n )
  y1 = np.sin ( x )
  y2 = np.cos ( x )
  plt.plot ( x, y1, 'r-' )  # Draw this curve in Red
  plt.plot ( x, y2, 'g-' )  # Draw this curve in Green
  plt.grid ( True )
  plt.title ( 'Trig fun' )
  filename = 'plot05.png'
  plt.show ( block = False )
  plt.savefig ( filename )
  print ( '  Graphics saved as "' + filename + '"' )
  plt.close ( )
#
#  Draw a curve and save the plot in a file.
#
  n = 101
  x = np.linspace ( 0.0, 2.0, n )
  y = 1.0 / ( ( x - 0.3 )**2 + 0.01 ) + 1.0 / ( ( x - 0.9 )**2 + 0.04 ) - 6.0
  plt.plot ( x, y, 'r-' )  # Draw this curve in Red
  plt.plot ( [0.0, 2.0], [0.0,0.0], 'k-' )  # Black line from (0,0) to (2,0)
  plt.plot ( [0.0, 0.0], [0.0,100.0], 'k-' )  # Black line from (0,0) to (0,100)
  plt.grid ( True )
  plt.title ( 'y = humps(x)' )
  filename = 'humps.png'
  plt.savefig ( filename )
  print ( '  Graphics saved as "' + filename + '"' )
  plt.show ( block = False )
  plt.close ( )
#
#  Draw two plots in one figure.
#
  x = np.linspace ( 0.0, 3.0, 101 )
  y1 = np.cos(x)+5*np.cos(1.6*x)-2*np.cos(2*x)+5*np.cos(4.5*x)+7*np.cos(9*x)
  y2 = - np.sin(x)-8*np.sin(1.6*x)+4*np.sin(2*x)-22.5*np.sin(4.5*x)-63*np.sin(9*x)
  fig = plt.figure ( )

  axes1 = fig.add_subplot ( 1, 2, 1 )  # on a (1x2) layout, this if the first subplot
  axes1.plot ( x, y1, 'r-' )
  axes1.set_title ( 'y1=f(x)' )
  axes1.grid ( True )

  axes2 = fig.add_subplot ( 1, 2, 2 )  # and this is the second subplot
  axes2.plot ( x, y2, 'b-' )
  axes2.set_title ( 'y2=dfdx(x)' )
  axes2.grid ( True )

  filename = 'two_plots.png'
  plt.savefig ( filename )
  print ( '  Graphics saved as "' + filename + '"' )
  plt.show ( block = False )
  plt.close ( )
#
#  Three plots.
#
  data = np.loadtxt ( fname = 'inflammation-01.csv', delimiter = ',' )
  y1 = np.max ( data, axis = 0 )
  y2 = np.mean ( data, axis = 0 )
  y3 = np.min ( data, axis = 0 )

  fig = plt.figure ( )

  axes1 = fig.add_subplot ( 1, 3, 1 )  # on a (1x3) layout, this if the first subplot
  axes1.plot ( y1, 'r-' )
  axes1.set_title ( 'Maximum' )
  axes1.grid ( True )

  axes2 = fig.add_subplot ( 1, 3, 2 )  # and this is the second subplot
  axes2.plot ( y2, 'b-' )
  axes2.set_title ( 'Mean' )
  axes2.grid ( True )

  axes3 = fig.add_subplot ( 1, 3, 3 )  # and this is the third subplot
  axes3.plot ( y3, 'g-' )
  axes3.set_title ( 'Minimum' )
  axes3.grid ( True )

  filename = 'three_plots.png'
  plt.savefig ( filename )
  print ( '  Graphics saved as "' + filename + '"' )
  plt.show ( block = False )
  plt.close ( )
  return

if ( __name__ == "__main__" ):
  python03 ( )