calcDoubleExcitation_withWeight Subroutine

    subroutine calcDoubleExcitation_withWeight(ilut, csf_i, excitInfo, excitations, &
                                               nExcits, posSwitches, negSwitches)
        ! subroutine to calculate the double excitations involving a weight
        ! generator, which is really similar so a normal single excitation
        integer(n_int), intent(in) :: ilut(0:nifguga)
        type(CSF_Info_t), intent(in) :: csf_i
        type(ExcitationInformation_t), intent(in) :: excitInfo
        integer(n_int), intent(out), allocatable :: excitations(:, :)
        integer, intent(out) :: nExcits
        real(dp), intent(in) :: posSwitches(nSpatOrbs), negSwitches(nSpatOrbs)

        integer :: iEx, we
        ! just call excitations first
        ! have to change excitInfo so single excitations are calculated
        ! correctly

        ! in future
        we = excitInfo%weight
        call calcAllExcitations(ilut, csf_i, excitInfo, posSwitches, negSwitches, &
                                .false., excitations, nExcits)

        ! and then modify the matrix element if necessary
        if ((excitInfo%weight /= excitInfo%fullStart) .and. (excitInfo%weight &
                                                             /= excitInfo%fullEnd)) then
            if (isThree(ilut, we)) then
                do iEx = 1, nExcits
                    call update_matrix_element(excitations(:, iEx), 2.0_dp, 1)
                end do
            end if
        end if

        ! also use the deltaB value of the finished excitations to indicate
        ! the IC level for the remaining NECI code
        do iEx = 1, nExcits
            ! is a single excitation in this case!
            call setDeltaB(1, excitations(:, iEx))
        end do

    end subroutine calcDoubleExcitation_withWeight