#! /usr/bin/env python3
#
from dolfin import *
from mshr import *

def domain ( ):

#*****************************************************************************80
#
## domain demonstrates creating a domain by "subtraction".
#
#  Licensing:
#
#    This code is distributed under the MIT license.
#
#  Modified:
#
#    23 October 2018
#
#  Author:
#
#    John Burkardt
#
  import matplotlib.pyplot as plt
#
#  Define a region as a circle "minus" a rectangle and a square.
#
  c1 = Point ( 0.0, 0.0 )
  r1 = 5.0
  sw = Point ( -3.0, -3.0 )
  ne = Point ( -2.0, 2.0 )
  c2 = Point ( 2.0, 2.0 )
  r2 = 1.0

  domain = Circle ( c1, r1, segments = 12 ) \
         - Rectangle ( sw, ne ) \
         - Circle ( c2, r2, segments = 12 )
#
#  Mesh the region.
#
  mesh = generate_mesh ( domain, 10 )
#
#  Plot the mesh.
#
  plot ( mesh, title = 'domain.py: logical combination of shapes' )
  filename = 'domain_mesh.png'
  plt.savefig ( filename )
  print ( '  Graphics saved as "%s"' % ( filename ) )
  plt.close ( )
#
#  Terminate.
#
  return

def domain_test ( ):

#*****************************************************************************80
#
## domain_test tests domain.
#
#  Licensing:
#
#    This code is distributed under the MIT license.
#
#  Modified:
#
#    23 October 2018
#
#  Author:
#
#    John Burkardt
#
  import dolfin
  import platform
  import time

  print ( time.ctime ( time.time() ) )
#
#  Report level = only warnings or higher.
#
  level = 30
  set_log_level ( level )

  print ( '' )
  print ( 'domain_test:' )
  print ( '  Python version: %s' % ( platform.python_version ( ) ) )
  print ( '  FENICS version %s'% ( dolfin.__version__ ) )
  print ( '  Demonstrate domain creattion by subtraction.' )

  domain ( )
#
#  Terminate.
#
  print ( '' )
  print ( 'domain_test:' )
  print ( '  Normal end of execution.' )
  print ( '' )
  print ( time.ctime ( time.time() ) )
  return

if ( __name__ == '__main__' ):

  domain_test ( )