tem_varSys_append_auxFieldVar Subroutine

  subroutine tem_varSys_append_auxFieldVar(me, varname, nComponents, &
    & method_data, get_point, get_element, set_params, get_params,   &
    & setup_indices, get_valOfIndex, pos, wasAdded)
    ! --------------------------------------------------------------------------!
    !> Variable system to append the state variable to.
    type(tem_varSys_type),             intent(inout) :: me

    !> Variable to append to the state.
    character(len=*),                  intent(in)    :: varname

    !> Number of components in this variable.
    integer, intent(in) :: nComponents

    !> Data that is required by the methods to obtain the variable.
    type(c_ptr), intent(in) :: method_data

    !> Procedure which allows the retrieval of the variable at given points.
    procedure(tem_varSys_proc_point), pointer :: get_point

    !> Procedure which allows the retrieval of the variable in an element.
    procedure(tem_varSys_proc_element), pointer :: get_element

    !> Procedure which allows to set parameter in method_data
    procedure(tem_varSys_proc_setParams), optional, pointer :: set_params

    !> Procedure which allows to get parameter in method_data
    procedure(tem_varSys_proc_getParams), optional, pointer :: get_params

    !> Procedure to setup growing array of points, variable value
    !! in method_data and return index of points set
    procedure(tem_varSys_proc_setupIndices), pointer :: setup_indices

    !> Procedure which allows to retrieval of the variable at point or val
    !! array index
    procedure(tem_varSys_proc_getValOfIndex), pointer :: get_valOfIndex

    !> Position of the variable in the system.
    integer,                 optional, intent(out)   :: pos

    !> Indicator, if the variable was actually added to the system.
    logical,                 optional, intent(out)   :: wasAdded
    ! --------------------------------------------------------------------------!
    logical :: newVar
    type(tem_varSys_op_type) :: auxField_access
    integer :: iComp, varPos
    ! --------------------------------------------------------------------------!

    call append( me       = me%varname, &
      &          val      = varname,    &
      &          pos      = varPos,     &
      &          wasAdded = newVar      )

    if (newVar) then
      auxField_access%mypos = varPos
      auxField_access%operType = 'auxfield'
      auxField_access%nInputs = 0
      auxField_access%nComponents = nComponents
      allocate(auxField_access%auxField_varPos(nComponents))
      do iComp = 1, nComponents
        auxField_access%auxField_varPos(iComp) = me%nAuxScalars + iComp
      end do
      allocate(auxField_access%input_varPos(0))

      auxField_access%method_data = method_data
      auxField_access%get_point => get_point
      auxField_access%get_element => get_element
      if (present(set_params)) then
        auxField_access%set_params => set_params
      else
        auxField_access%set_params => tem_varSys_setParams_dummy
      end if
      if (present(get_params)) then
        auxField_access%get_params => get_params
      else
        auxField_access%get_params => tem_varSys_getParams_dummy
      end if
      auxField_access%setup_indices => setup_indices
      auxField_access%get_valOfIndex => get_valOfIndex
      call append( me  = me%method,   &
        &          val = auxField_access )
      me%nAuxVars = me%nAuxVars+1
      me%nAuxScalars = me%nAuxScalars + nComponents
    end if

    if (present(pos)) pos = varPos
    if (present(wasAdded)) wasAdded = newVar

  end subroutine tem_varSys_append_auxFieldVar