expand_corespace_buf Subroutine

    subroutine expand_corespace_buf(buffer, buffer_size)
        use real_time_data, only: ssht, wn_threshold
        use real_time_aux, only: add_semistochastic_state
        use FciMCData, only: AllTotParts
        implicit none
        integer(n_int), intent(inout) :: buffer(0:, 1:)
        integer, intent(inout) :: buffer_size
        integer(int64) :: i
        real(dp) :: sgn(lenof_sign)

        do i = 1, TotWalkers
            call extract_sign(CurrentDets(:, i), sgn)
            if (sum(abs(sgn)) / inum_runs > wn_threshold * sum(abs(AllTotParts)) / inum_runs) then
                call add_semistochastic_state(buffer, buffer_size, ssht, CurrentDets(:, i))
            end if
        end do

    end subroutine expand_corespace_buf