#! /usr/bin/env python
#
def ubvec_enum ( n ):

#*****************************************************************************80
#
## UBVEC_ENUM enumerates the unsigned binary vectors of length N.
#
#  Discussion:
#
#    A UBVEC is a vector of N binary digits.
#
#    A UBVEC can be interpreted as a binary representation of an
#    unsigned integer, with the first entry being the coefficient of
#    2^(N-1) and the last entry the coefficient of 1.
#
#    UBVEC   #
#    -----  --
#    00000   0
#    00001   1
#    00010   2
#    10000  16
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    22 November 2015
#
#  Author:
#
#    John Burkardt
#
#  Parameters:
#
#    Input, integer N, the length of the vectors.
#
#    Output, integer VALUE, the number of binary vectors.
#
  value = 2 ** n

  return value

def ubvec_enum_test ( ):

#*****************************************************************************80
#
## UBVEC_ENUM_TEST tests UBVEC_ENUM.
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license. 
#
#  Modified:
#
#    22 November 2015
#
#  Author:
#
#    John Burkardt
#
  import platform

  print ( '' )
  print ( 'UBVEC_ENUM_TEST' )
  print ( '  Python version: %s' % ( platform.python_version ( ) ) )
  print ( '  UBVEC_ENUM enumerates unsigned binary vectors' )
  print ( '  of N digits' )
  print ( '' )
  print ( '   N      Number' )
  print ( '' )

  for n in range ( 0, 11 ):
    
    n2 = ubvec_enum ( n )

    print ( '  %2d  %8d' % ( n, n2 ) )
#
#  Terminate.
#
  print ( '' )
  print ( 'UBVEC_ENUM_TEST' )
  print ( '  Normal end of execution.' )
  return

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