set_conn_init_space_flags_slow Subroutine

public subroutine set_conn_init_space_flags_slow(ilut_list, list_size)


Type IntentOptional Attributes Name
integer(kind=n_int), intent(inout) :: ilut_list(0:,:)
integer, intent(in) :: list_size


Source Code

    subroutine set_conn_init_space_flags_slow(ilut_list, list_size)

        use bit_reps, only: set_flag, get_initiator_flag
        use DetBitOps, only: CountBits, TestClosedShellDet

        ! Set initiator flags for any determinants in ilut_list which are
        ! connected to states within the initiator space

        integer(n_int), intent(inout) :: ilut_list(0:, :)
        integer, intent(in) :: list_size

        integer :: i, j, part_type, IC
        integer(n_int) :: tmp(0:NIfD)

        do i = 1, list_size
            ! If the initiator flag is already set, then we don't need to check
            ! whether or not to set it
            if (test_flag(ilut_list(:, i), get_initiator_flag(1))) cycle

            ! First the naive way: just check every single state in the initiator space...
            do j = 1, initiator_space_size
                tmp = ieor(ilut_list(0:NIfD, i), initiator_space(0:NIfD, j))
                tmp = iand(ilut_list(0:NIfD, i), tmp)
                IC = CountBits(tmp, NIfD)
                if (IC <= 2) then
                    do part_type = 1, lenof_sign
                        call set_flag(ilut_list(:, i), get_initiator_flag(part_type))
                    end do
                end if
            end do
        end do

    end subroutine set_conn_init_space_flags_slow