#! /usr/bin/env python
#
def i4_sign ( i ):

#*****************************************************************************80
#
## I4_SIGN returns the sign of an integer.
#
#  Discussion:
#
#    The value is +1 if the number is positive or zero, and it is -1 otherwise.
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    05 April 2013
#
#  Author:
#
#    John Burkardt
#
#  Parameters:
#
#    Input, integer I, the number whose sign is desired.
#
#    Output, integer VALUE, the sign of I.
#
  if ( i < 0 ):
    value = -1
  else:
    value = +1

  return value

def i4_sign_test ( ):

#*****************************************************************************80
#
## I4_SIGN_TEST tests I4_SIGN.
#
#  Licensing:
#
#    This code is distributed under the GNU LGPL license.
#
#  Modified:
#
#    28 September 2014
#
#  Author:
#
#    John Burkardt
#
  import numpy as np
  import platform

  test_num = 5

  i4_vec = np.array ( ( -10, -7, 0, 5, 9 ) )

  print ( '' )
  print ( 'I4_SIGN_TEST' )
  print ( '  Python version: %s' % ( platform.python_version ( ) ) )
  print ( '  I4_SIGN returns the sign of an I4.' )
  print ( '' )
  print ( '    I4  I4_SIGN(I4)' )
  print ( '' )

  for test in range ( 0, test_num ):
    i4 = i4_vec[test]
    s = i4_sign ( i4 )
    print ( '  %4d  %11d' % ( i4, s ) )
#
#  Terminate.
#
  print ( '' )
  print ( 'I4_SIGN_TEST' )
  print ( '  Normal end of execution.' )
  return

if ( __name__ == '__main__' ):
  from timestamp import timestamp
  timestamp ( )
  i4_sign_test ( )
  timestamp ( )