#! /usr/bin/env python
#
def i1ml1_values ( n_data ):

#*****************************************************************************80
#
## I1ML1_VALUES returns some values of the I1ML1 function.
#
#  Discussion:
#
#    The function is defined by:
#
#      I1ML1(x) = I1(x) - L1(x)
#
#    I1(x) is the modified Bessel function of the first kind of order 1, 
#    L1(x) is the modified Struve function of order 1.
#
#    The data was reported by McLeod.
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    15 February 2015
#
#  Author:
#
#    John Burkardt
#
#  Reference:
#
#    Allan McLeod,
#    Algorithm 757, MISCFUN: A software package to compute uncommon
#      special functions,
#    ACM Transactions on Mathematical Software,
#    Volume 22, Number 3, September 1996, pages 288-301.
#
#  Parameters:
#
#    Input/output, integer N_DATA.  The user sets N_DATA to 0 before the
#    first call.  On each call, the routine increments N_DATA by 1, and
#    returns the corresponding data; when there is no more data, the
#    output value of N_DATA will be 0 again.
#
#    Output, real X, the argument of the function.
#
#    Output, real F, the value of the function.
#
  import numpy as np

  n_max = 20

  f_vec = np.array ( (\
     0.97575346155386267134E-03, \
     0.77609293280609272733E-02, \
     0.59302966404545373770E-01, \
     0.20395212276737365307E+00, \
     0.33839472293667639038E+00, \
     0.48787706726961324579E+00, \
     0.59018734196576517506E+00, \
     0.62604539530312149476E+00, \
     0.63209315274909764698E+00, \
     0.63410179313235359215E+00, \
     0.63417966797578128188E+00, \
     0.63439268632392089434E+00, \
     0.63501579073257770690E+00, \
     0.63559616677359459337E+00, \
     0.63591001826697110312E+00, \
     0.63622113181751073643E+00, \
     0.63636481702133606597E+00, \
     0.63650653499619902120E+00, \
     0.63655609126300261851E+00, \
     0.63657902087183929223E+00 ))

  x_vec = np.array ( (\
       0.0019531250E+00, \
       0.0156250000E+00, \
       0.1250000000E+00, \
       0.5000000000E+00, \
       1.0000000000E+00, \
       2.0000000000E+00, \
       4.0000000000E+00, \
       8.0000000000E+00, \
      12.0000000000E+00, \
      16.0000000000E+00, \
      16.2500000000E+00, \
      17.0000000000E+00, \
      20.0000000000E+00, \
      25.0000000000E+00, \
      30.0000000000E+00, \
      40.0000000000E+00, \
      50.0000000000E+00, \
      75.0000000000E+00, \
     100.0000000000E+00, \
     125.0000000000E+00 ))

  if ( n_data < 0 ):
    n_data = 0

  if ( n_max <= n_data ):
    n_data = 0
    x = 0.0
    f = 0.0
  else:
    x = x_vec[n_data]
    f = f_vec[n_data]
    n_data = n_data + 1

  return n_data, x, f

def i1ml1_values_test ( ):

#*****************************************************************************80
#
## I1ML1_VALUES_TEST demonstrates the use of I1ML1_VALUES.
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    15 February 2015
#
#  Author:
#
#    John Burkardt
#
  import platform

  print ( '' )
  print ( 'I1ML1_VALUES_TEST:' )
  print ( '  Python version: %s' % ( platform.python_version ( ) ) )
  print ( '  I1ML1_VALUES stores values of the I1ML1 function.' )
  print ( '' )
  print ( '      X         I1ML1(X)' )
  print ( '' )

  n_data = 0

  while ( True ):

    n_data, x, fx = i1ml1_values ( n_data )

    if ( n_data == 0 ):
      break

    print ( '  %12f  %24.16f' % ( x, fx ) )
#
#  Terminate.
#
  print ( '' )
  print ( 'I1ML1_VALUES_TEST:' )
  print ( '  Normal end of execution.' )
  return

if ( __name__ == '__main__' ):
  from timestamp import timestamp
  timestamp ( )
  i1ml1_values_test ( )
  timestamp ( )