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

#*****************************************************************************80
#
## ARCCOSH_VALUES returns some values of the hyperbolic arc cosine function.
#
#  Discussion:
#
#    In Mathematica, the function can be evaluated by:
#
#      ArcCosh[x]
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    21 December 2014
#
#  Author:
#
#    John Burkardt
#
#  Reference:
#
#    Milton Abramowitz, Irene Stegun,
#    Handbook of Mathematical Functions,
#    National Bureau of Standards, 1964,
#    ISBN: 0-486-61272-4,
#    LC: QA47.A34.
#
#    Stephen Wolfram,
#    The Mathematica Book,
#    Fourth Edition,
#    Cambridge University Press, 1999,
#    ISBN: 0-521-64314-7,
#    LC: QA76.95.W65.
#
#  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 value of the function.
#
  import numpy as np

  n_max = 15

  fx_vec = np.array ( ( \
    0.0000000000000000000, \
    0.14130376948564857735, \
    0.44356825438511518913, \
    0.62236250371477866781, \
    0.75643291085695958624, \
    0.86701472649056510395, \
    0.96242365011920689500, \
    1.3169578969248167086, \
    1.7627471740390860505, \
    1.8115262724608531070, \
    2.0634370688955605467, \
    2.2924316695611776878, \
    2.9932228461263808979, \
    5.2982923656104845907, \
    7.6009022095419886114 ) )

  x_vec = np.array ( ( \
       1.0, \
       1.01, \
       1.1, \
       1.2, \
       1.3, \
       1.4, \
       1.5, \
       2.0, \
       3.0, \
       3.1415926535897932385, \
       4.0, \
       5.0, \
      10.0, \
     100.0, \
    1000.0 ) )

  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 arccosh_values_test ( ):

#*****************************************************************************80
#
## ARCCOSH_VALUES_TEST tests ARCCOSH_VALUES.
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    21 December 2014
#
#  Author:
#
#    John Burkardt
#
  import platform

  print ( '' )
  print ( 'ARCCOSH_VALUES_TEST:' )
  print ( '  Python version: %s' % ( platform.python_version ( ) ) )
  print ( '  ARCCOSH_VALUES stores values of' )
  print ( '  the hyperbolic arc cosine function.' )
  print ( '' )
  print ( '        X               F(X)' )
  print ( '' )

  n_data = 0

  while ( True ):

    n_data, x, fx = arccosh_values ( n_data )

    if ( n_data == 0 ):
      break

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

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