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

#*****************************************************************************80
#
## AIRY_BI_PRIME_VALUES returns some values of the Airy function Bi'(x).
#
#  Discussion:
#
#    The Airy functions Ai(X) and Bi(X) are a pair of linearly independent
#    solutions of the differential equation:
#
#      W'' - X * W = 0
#
#    In Mathematica, the function can be evaluated by:
#
#      AiryBiPrime[x]
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    16 December 2014
#
#  Author:
#
#    John Burkardt
#
#  Reference:
#
#    Milton Abramowitz and Irene Stegun,
#    Handbook of Mathematical Functions,
#    US Department of Commerce, 1964.
#
#    Stephen Wolfram,
#    The Mathematica Book,
#    Fourth Edition,
#    Wolfram Media / Cambridge University Press, 1999.
#
#  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 FX, the derivative of the Airy BI function.
#
  import numpy as np

  n_max = 11

  fx_vec = np.array ( ( \
     0.4482883573538264E+00, \
     0.4515126311496465E+00, \
     0.4617892843621509E+00, \
     0.4800490287524480E+00, \
     0.5072816760506224E+00, \
     0.5445725641405923E+00, \
     0.5931444786342857E+00, \
     0.6544059191721400E+00, \
     0.7300069016152518E+00, \
     0.8219038903072090E+00, \
     0.9324359333927756E+00 ) )

  x_vec = np.array ( ( \
     0.0E+00, \
     0.1E+00, \
     0.2E+00, \
     0.3E+00, \
     0.4E+00, \
     0.5E+00, \
     0.6E+00, \
     0.7E+00, \
     0.8E+00, \
     0.9E+00, \
     1.0E+00 ) )

  if ( n_data < 0 ):
    n_data = 0

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

  return n_data, x, fx

def airy_bi_prime_values_test ( ):

#*****************************************************************************80
#
## AIRY_BI_PRIME_VALUES_TEST demonstrates the use of AIRY_BI_PRIME_VALUES.
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    16 December 2014
#
#  Author:
#
#    John Burkardt
#
  import platform

  print ( '' )
  print ( 'AIRY_BI_PRIME_VALUES_TEST:' )
  print ( '  Python version: %s' % ( platform.python_version ( ) ) )
  print ( '  AIRY_BI_PRIME_VALUES stores values of' )
  print ( '  the derivative of the Airy Bi function.' )
  print ( '' )
  print ( '      X           FX' )
  print ( '' )

  n_data = 0

  while ( True ):

    n_data, x, fx = airy_bi_prime_values ( n_data )

    if ( n_data == 0 ):
      break

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

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