#! /usr/bin/env python
#
def triangle_monte_carlo_test02 ( ):

#*****************************************************************************80
#
## TRIANGLE_MONTE_CARLO_TEST02 samples a general triangle.
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    18 July 2018
#
#  Author:
#
#    John Burkardt
#
  import numpy as np
  from r8mat_transpose_print import r8mat_transpose_print
  from triangle_monte_carlo import triangle_monte_carlo

  t = np.array ( [ \
    [ 2.0, 3.0, 0.0 ], \
    [ 0.0, 4.0, 3.0 ] ] )

  r8mat_transpose_print ( 2, 3, t, '  Triangle vertices:' )

  print ( '' )
  print ( 'TRIANGLE_MONTE_CARLO_TEST02' )
  print ( '  Integrate xy^3' )
  print ( '  Integration region is a general triangle.' )
  print ( '  Use an increasing number of points N.' )

  seed = 123456789

  print ( '' )
  print ( '     N          XY^3' )
  print ( '' )

  n = 1

  while ( n <= 65536 ):

    result, seed = triangle_monte_carlo ( t, n, triangle_integrand, seed )

    print ( '  %8d  %14f' % ( n, result ) )

    n = 2 * n

  return

def triangle_integrand ( p ):

#*****************************************************************************80
#
## TRIANGLE_INTEGRAND evaluates xy^3
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    15 August 2009
#
#  Author:
#
#    John Burkardt
#
#  Parameters:
#
#    Input, real P(2,P_NUM), the evaluation points.
#
#    Output, real FP(P_NUM), the integrand values.
#
  fp = p[0,:] * p[1,:] ** 3

  return fp

if ( __name__ == '__main__' ):
  from timestamp import timestamp
  timestamp ( )
  triangle_monte_carlo_test02 ( )
  timestamp ( )