subroutine tetrahedron_array_small_init(tet_array_small)
implicit none
integer, dimension(6, 4), intent(inout) :: tet_array_small
! without correction
! z !
! 7----------8 ! tetrahedron #1: 1-5-6-8
tet_array_small(1, :) = (/1, 5, 6, 8/) ! /| /| layer 2! tetrahedron #2: 1-7-5-8
tet_array_small(2, :) = (/1, 7, 5, 8/) ! 5----------6 | ! tetrahedron #3: 1-3-7-8
tet_array_small(3, :) = (/1, 3, 7, 8/) ! | | y | | ! tetrahedron #4: 1-4-3-8
tet_array_small(4, :) = (/1, 4, 3, 8/) ! | 3--------|-4 ! tetrahedron #5: 1-2-4-8
tet_array_small(5, :) = (/1, 2, 4, 8/) ! |/ |/ layer 1! tetrahedron #6: 1-6-2-8
tet_array_small(6, :) = (/1, 6, 2, 8/) ! 1----------2 x !
! 1-8 : main diagonal !
!=============================!
end subroutine tetrahedron_array_small_init
