utility_translate_home Subroutine

  subroutine utility_translate_home(vec, real_lat, recip_lat)
    !========================================================!
    !                                                        !
    !! Translate a vector to the home unit cell
    !                                                        !
    !========================================================!

    implicit none

    real(kind=dp), intent(inout) :: vec(3)
    real(kind=dp), intent(in)    :: real_lat(3, 3)
    real(kind=dp), intent(in)    :: recip_lat(3, 3)

    ! <<<local variables>>>
    integer       :: ind
    real(kind=dp) :: r_home(3), r_frac(3)
    real(kind=dp) :: shift

    r_home = 0.0_dp; r_frac = 0.0_dp

    ! Cartesian --> fractional
    call utility_cart_to_frac(vec, r_frac, recip_lat)
    ! Rationalise to interval [0,1]
    do ind = 1, 3
      if (r_frac(ind) .lt. 0.0_dp) then
        shift = real(ceiling(abs(r_frac(ind))), kind=dp)
        r_frac(ind) = r_frac(ind) + shift
      endif
      if (r_frac(ind) .gt. 1.0_dp) then
        shift = -real(int(r_frac(ind)), kind=dp)
        r_frac(ind) = r_frac(ind) + shift
      endif
    enddo
    ! Fractional --> Cartesian
    call utility_frac_to_cart(r_frac, r_home, real_lat)

    vec = r_home

    return
  end subroutine utility_translate_home