module circle_constant
  real, parameter :: pi = 3.14159

  type meta_data
    character(len=10) :: color
    real :: circumference
    real :: diameter
    real :: radius
    real :: area
  end type meta_data

  contains
    subroutine meta_comp(r, item)
       type(meta_data) :: item
       item%diameter = 2.0 * r
       item%area = pi * r **2
       item%circumference = 2.0 * pi * r
    end subroutine

  end module circle_constant

  program circle_comp
! make the content of module available
  use circle_constant
  real :: r
  integer :: iloop
  type(meta_data), dimension(10) :: circles
!
  r = 2.0
  circles(1)%radius = 4
  circles(1)%color = "red"
  call meta_comp(r, circles(1))  ! Call the module function

  circles(2:10)%color = "blue"   ! array operation
  r = 4.0
  circles(2:10)%radius = r       ! array operation
  do iloop=2,10
     call meta_comp(r,circles(iloop))
  end do

  end program circle_comp