initialize_type_domain Subroutine

    subroutine initialize_type_domain(self, input, Coordinate, ierr)
        implicit none
        class(type_domain), intent(inout) :: self
        type(type_input), intent(in) :: input
        type(type_dp_3d), intent(inout), pointer :: Coordinate
        integer(int32), intent(inout) :: ierr

        type(type_crs_adjacency_element) :: element_adjacency
        type(type_node_adjacency) :: node_adjacency

        integer(int32) :: count_sides, count_elements, count_volumes
        integer(int32) :: iCell, iElem, iSide
        integer(int32) :: factory_ierr
        integer(int32) :: cell_dimension

        ! -----------------------------------------------------------------------------------
        ! 初期化処理
        ! -----------------------------------------------------------------------------------
        ierr = 0
        count_sides = 0
        count_elements = 0
        count_volumes = 0

        do iCell = 1, input%geometry%vtk%num_total_cells
            cell_dimension = input%geometry%vtk%cells(iCell)%get_dimension()
            select case (cell_dimension)
            case (1)
                count_sides = count_sides + 1
            case (2)
                count_elements = count_elements + 1
            case (3)
                count_volumes = count_volumes + 1
            end select
        end do

        self%num_elements = count_elements
        self%num_sides = count_sides
        self%num_nodes = input%geometry%vtk%num_points
        self%num_materials = input%basic%num_materials

        if (allocated(self%elements)) deallocate (self%elements)
        allocate (self%elements(self%num_elements))
        if (allocated(self%sides)) deallocate (self%sides)
        allocate (self%sides(self%num_sides))

        iElem = 1
        iSide = 1
        do iCell = 1, input%geometry%vtk%num_total_cells
            cell_dimension = input%geometry%vtk%cells(iCell)%get_dimension()
            select case (cell_dimension)
            case (1)
                call create_side(new_side=self%sides(iSide)%s, &
                                 id=iCell, &
                                 global_coordinate=Coordinate, &
                                 cell_info=input%geometry%vtk%cells(iCell), &
                                 integration=input%basic%geometry_settings, &
                                 ierr=factory_ierr)
                if (factory_ierr /= 0) then
                    ierr = -1
                    return
                end if
                iSide = iSide + 1
            case (2)
                call create_element(new_element=self%elements(iElem)%e, &
                                    id=iCell, &
                                    global_coordinate=Coordinate, &
                                    cell_info=input%geometry%vtk%cells(iCell), &
                                    integration=input%basic%geometry_settings, &
                                    ierr=factory_ierr)
                if (factory_ierr /= 0) then
                    ierr = -1
                    return
                end if
                iElem = iElem + 1
            case (3)
                !!TBI
            end select

        end do

        self%computaion_dimension = input%basic%simulation_settings%calculate_dimension

        !===============================================================
        ! 3. 隣接行列の構築
        !===============================================================
        call element_adjacency%initialize(self%elements)
        print *, "Step 3a: Element adjacency matrix created."

        !===============================================================
        ! 4. RCM並べ替えの実行
        !===============================================================
        call self%reordering%initialize(input%basic%solver_settings%reordering, self%elements)
        if (input%basic%solver_settings%reordering /= "none") then
            call self%apply_reordering()
            call global_logger%log_information(message="RCM reordering completed.")
        end if

        !===============================================================
        ! 5. グラフ彩色の実行
        !===============================================================
        call self%colors%initialize(input%basic%solver_settings%coloring, element_adjacency)
        call global_logger%log_information(message="Graph coloring completed using " &
                                           //trim(self%colors%algorithm_name)//" algorithm.")

        !===============================================================
        ! 6. 後片付け
        !===============================================================
        call global_logger%log_information(message="Initialization process completed successfully.")

    end subroutine initialize_type_domain