program main

!*****************************************************************************80
!
!! cosine_transform_test() tests cosine_transform().
!
!  Licensing:
!
!    This code is distributed under the MIT license.
!
!  Modified:
!
!    26 August 2015
!
!  Author:
!
!    John Burkardt
!
  implicit none

  call timestamp ( )
  write ( *, '(a)' ) ''
  write ( *, '(a)' ) 'cosine_transform_test():'
  write ( *, '(a)' ) '  Fortran90 version.'
  write ( *, '(a)' ) '  Test cosine_transform().'

  call cosine_transform_test01 ( )
!
!  Terminate.
!
  write ( *, '(a)' ) ''
  write ( *, '(a)' ) 'cosine_transform_test():'
  write ( *, '(a)' ) '  Normal end of execution.'
  write ( *, '(a)' ) ''
  call timestamp ( )

  stop 0
end
subroutine cosine_transform_test01 ( )

!*****************************************************************************80
!
!! COSINE_TRANSFORM_TEST01 does a DCT and its inverse.
!
!  Licensing:
!
!    This code is distributed under the MIT license.
!
!  Modified:
!
!    26 August 2015
!
!  Author:
!
!    John Burkardt
!
  implicit none

  integer, parameter :: rk = kind ( 1.0D+00 )

  integer, parameter :: n = 10

  integer i
  real ( kind = rk ) r(n)
  real ( kind = rk ) s(n)
  real ( kind = rk ) t(n)

  write ( *, '(a)' ) ''
  write ( *, '(a)' ) 'COSINE_TRANSFORM_TEST01:'
  write ( *, '(a)' ) '  COSINE_TRANSFORM_DATA does a cosine transform of data'
  write ( *, '(a)' ) '  defined by a vector.'
  write ( *, '(a)' ) ''
  write ( *, '(a)' ) '  Apply the transform, then its inverse.'
  write ( *, '(a)' ) '  Let R be a random N vector.'
  write ( *, '(a)' ) '  Let S be the transform of D.'
  write ( *, '(a)' ) '  Let T be the transform of E.'
  write ( *, '(a)' ) '  Then R and T will be equal.'

  call random_number ( harvest = r(1:n) )
  call cosine_transform_data ( n, r, s )
  call cosine_transform_inverse ( n, s, t )

  write ( *, '(a)' ) ''
  write ( *, '(a)' ) '     I      R(I)        S(I)        T(I)'
  write ( *, '(a)' ) ''

  do i = 1, n
    write ( *, '(2x,i4,2x,f10.6,2x,f10.6,2x,f10.6)' ) i, r(i), s(i), t(i)
  end do

  return
end
subroutine timestamp ( )

!*****************************************************************************80
!
!! timestamp() prints the current YMDHMS date as a time stamp.
!
!  Example:
!
!    31 May 2001   9:45:54.872 AM
!
!  Licensing:
!
!    This code is distributed under the MIT license.
!
!  Modified:
!
!    18 May 2013
!
!  Author:
!
!    John Burkardt
!
  implicit none

  character ( len = 8 ) ampm
  integer d
  integer h
  integer m
  integer mm
  character ( len = 9 ), parameter, dimension(12) :: month = (/ &
    'January  ', 'February ', 'March    ', 'April    ', &
    'May      ', 'June     ', 'July     ', 'August   ', &
    'September', 'October  ', 'November ', 'December ' /)
  integer n
  integer s
  integer values(8)
  integer y

  call date_and_time ( values = values )

  y = values(1)
  m = values(2)
  d = values(3)
  h = values(5)
  n = values(6)
  s = values(7)
  mm = values(8)

  if ( h < 12 ) then
    ampm = 'AM'
  else if ( h == 12 ) then
    if ( n == 0 .and. s == 0 ) then
      ampm = 'Noon'
    else
      ampm = 'PM'
    end if
  else
    h = h - 12
    if ( h < 12 ) then
      ampm = 'PM'
    else if ( h == 12 ) then
      if ( n == 0 .and. s == 0 ) then
        ampm = 'Midnight'
      else
        ampm = 'AM'
      end if
    end if
  end if

  write ( *, '(i2.2,1x,a,1x,i4,2x,i2,a1,i2.2,a1,i2.2,a1,i3.3,1x,a)' ) &
    d, trim ( month(m) ), y, h, ':', n, ':', s, '.', mm, trim ( ampm )

  return
end