cell_inf_hex18.h

一个用来实现偏微分方程中网格的计算库

// $Id: cell_inf_hex18.h 2788 2008-04-13 02:05:22Z roystgnr $

// The libMesh Finite Element Library.
// Copyright (C) 2002-2007  Benjamin S. Kirk, John W. Peterson
  
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
  
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
  
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA



#ifndef __cell_inf_hex18_h__
#define __cell_inf_hex18_h__

// C++ includes

// Local includes
#include "libmesh_config.h"
#ifdef ENABLE_INFINITE_ELEMENTS

#include "cell_inf_hex.h"




/**
 * The \p InfHex18 is an infinite element in 3D composed of 18 nodes.
 * It is numbered like this:
   \verbatim
   INFHEX18:   7              14             6     			      
               o              o              o     closer to infinity
               :              :              |     	
               :              :              |     	
               :              :              |     	 
         15    :        17    :        13    |         
          o    :         o    :         o    |     	
          :    :              :         |    |     	
          :    :              :         |    |     
          :    :              :         |    |     
     4    :    :   12         :    5    |    |     
     o    :    :    o         :    o    |    |         
     |    :    :    |         :    |    |    |     
     |    :    :    |         :    |    |    |     
     |    :    :    |       10:    |    |    |           
     |    :   3o....|.........o....|....|....o    
     |    :   .     |              |    |   / 2      
     |    :  .      |              |    |  /        
     |    : .       |              |    | /         
     |    :.        |              |    |/          
     |  11o         |  16o         |    o           base face
     |   .          |              |   / 9          
     |  .           |              |  /             
     | .            |              | /              
     |.             |              |/               
     o--------------o--------------o                
     0              8              1                
   \endverbatim
 */

// ------------------------------------------------------------
// InfHex18 class definition
class InfHex18 : public InfHex
{
public:

  /**
   * Constructor.  By default this element has no parent.
   */
  InfHex18  (Elem* p=NULL);
    
  /**
   * @returns 18.  The \p InfHex18 has 18 nodes.
   */
  unsigned int n_nodes() const { return 18; }
  
  /**
   * @returns \p INFHEX18
   */
  ElemType     type ()   const { return INFHEX18; }
  
  /**
   * @returns 4
   */
  unsigned int n_sub_elem() const { return 4; }
  
  /**
   * @returns SECOND
   */
  Order default_order() const { return SECOND; }

  /**
   * @returns true iff the specified (local) node number is a vertex.
   */
  virtual bool is_vertex(const unsigned int i) const;

  /**
   * @returns true iff the specified (local) node number is an edge.
   */
  virtual bool is_edge(const unsigned int i) const;

  /**
   * @returns true iff the specified (local) node number is a face.
   */
  virtual bool is_face(const unsigned int i) const;
  
  /*
   * @returns true iff the specified (local) node number is on the
   * specified side
   */
  virtual bool is_node_on_side(const unsigned int n,
			       const unsigned int s) const;
  
  /*
   * @returns true iff the specified (local) node number is on the
   * specified edge
   */
  virtual bool is_node_on_edge(const unsigned int n,
			       const unsigned int e) const;
  
  /**
   * Returns a \p QUAD9 built coincident with face 0, an \p INFQUAD6 
   * built coincident with faces 1 to 4. Note that the \p AutoPtr<Elem>
   * takes care of freeing memory.
   */
  AutoPtr<Elem> build_side (const unsigned int i,
			    bool proxy) const;

  /**
   * Returns a \p EDGE3 built coincident with edges 0-3, an \p INFEDGE2 
   * built coincident with edges 4 to 11. Note that the \p AutoPtr<Elem>
   * takes care of freeing memory.
   */
  AutoPtr<Elem> build_edge (const unsigned int i) const;

  /**
   * @returns an id associated with the \p s side of this element.
   * The id is not necessariy unique, but should be close.  This is
   * particularly useful in the \p MeshBase::find_neighbors() routine.
   *
   * We reimplemenet this method here for the \p InfHex18 since we can
   * use the center node of the bottom face to provide a perfect (unique)
   * key.
   */
  unsigned int key (const unsigned int s) const;

  virtual void connectivity(const unsigned int sc,
			    const IOPackage iop,
			    std::vector<unsigned int>& conn) const;

//   void tecplot_connectivity(const unsigned int sc,
// 			    std::vector<unsigned int>& conn) const;

//   void vtk_connectivity(const unsigned int,
// 			std::vector<unsigned int>*) const
//   { libmesh_error(); }
  
  unsigned int vtk_element_type (const unsigned int) const
  { return 12; }

  /**
   * @returns 2 for all edge nodes, 4 for face nodes
   */
  unsigned int n_second_order_adjacent_vertices (const unsigned int) const;

  /**
   * @returns the element-local number of the  \f$ v^{th} \f$ vertex
   * that defines the \f$ n^{th} \f$ second-order node.
   * Note that \p n is counted as depicted above, \f$ 8 \le n < 18 \f$.
   */
  unsigned short int second_order_adjacent_vertex (const unsigned int n,
						   const unsigned int v) const;

  /**
   * @returns the child number \p c and element-local index \p v of the
   * \f$ n^{th} \f$ second-order node on the parent element.  Note that
   * the return values are always less \p this->n_children() and 
   * \p this->child(c)->n_vertices(), while \p n has to be greater or equal
   * to \p * this->n_vertices().  For linear elements this returns 0,0.
   * On refined second order elements, the return value will satisfy
   * \p this->get_node(n)==this->child(c)->get_node(v)
   */
  virtual std::pair<unsigned short int, unsigned short int> 
	  second_order_child_vertex (const unsigned int n) const;

  /**
   * This maps the \f$ j^{th} \f$ node of the \f$ i^{th} \f$ side to
   * element node numbers.
   */
  static const unsigned int side_nodes_map[5][9];

  /**
   * This maps the \f$ j^{th} \f$ node of the \f$ i^{th} \f$ edge to
   * element node numbers.
   */
  static const unsigned int edge_nodes_map[8][3];
   

protected:
  
  
#ifdef ENABLE_AMR

  /**
   * Matrix used to create the elements children.
   */
  float embedding_matrix (const unsigned int i,
			  const unsigned int j,
			  const unsigned int k) const
  { return _embedding_matrix[i][j][k]; }

  /**
   * Matrix that computes new nodal locations/solution values
   * from current nodes/solution.
   */
  static const float _embedding_matrix[4][18][18];
  
  
#endif

};



// ------------------------------------------------------------
// InfHex18 class member functions
inline
InfHex18::InfHex18(Elem* p) :
  InfHex(InfHex18::n_nodes(), p) 
{
}


#endif  // ifdef ENABLE_INFINITE_ELEMENTS


#endif