!===============================================
! dotprod.f90

! dot product using kind to set precision
!===============================================
program dotprod
  implicit none

  !---------------------------
  ! set kind
  !---------------------------
  integer, parameter :: rk = selected_real_kind(12)

  integer :: i
  real(rk) :: c
  real(rk), dimension(3) :: a, b

  !----------------------------
  ! input vectors
  !----------------------------
  print*,'Enter first vector'
  read*, a
  print*,'Enter second vector'
  read*, b

  !----------------------------
  ! calculate dot product
  !----------------------------
  call dp(a,b,c)

  !----------------------------
  ! check magnitude
  !----------------------------
  if(abs(c) < 1.0e-6) then
     print*,'---------------------------------------------------'
     print*,'Warning: magnitude of dot product is less than 1e-6'
     print*,'---------------------------------------------------'
  endif

  !----------------------------
  ! print result
  !----------------------------
  print*,' '
  print*,'dot product = ', c

end program dotprod