Init_TwoPointVector3D_t Subroutine

  subroutine Init_TwoPointVector3D_t(this,interp,nVar,nElem)
    !! Allocate the interior array for a 3-D two-point vector field.
    !! The interior array has rank 7 with layout (n,i,j,k,nEl,nVar,idir).
    !!
    !! Requires Gauss-Lobatto quadrature nodes (controlNodeType=GAUSS_LOBATTO).
    implicit none
    class(TwoPointVector3D_t),intent(out) :: this
    type(Lagrange),target,intent(in) :: interp
    integer,intent(in) :: nVar
    integer,intent(in) :: nElem
    ! Local
    integer :: i

    if(interp%controlNodeType /= GAUSS_LOBATTO) then
      print*,__FILE__//" : TwoPointVector3D requires Gauss-Lobatto quadrature nodes."
      stop 1
    endif

    this%interp => interp
    this%nVar = nVar
    this%nElem = nElem
    this%N = interp%N
    this%M = interp%M

    allocate(this%interior(1:interp%N+1,1:interp%N+1,1:interp%N+1,1:interp%N+1, &
                           1:nElem,1:nVar,1:3))

    allocate(this%meta(1:nVar))
    allocate(this%eqn(1:3*nVar))

    ! Initialize equation parser to prevent segmentation faults with amdflang
    ! when the parser functions are not allocated (see SELF_Vector_2D_t.f90)
    do i = 1,3*nVar
      this%eqn(i) = EquationParser('f=0',(/'x','y','z','t'/))
    enddo

    this%interior = 0.0_prec

  endsubroutine Init_TwoPointVector3D_t