J:/Tecgraf/prj/femoop/trunk/shp/shpquads.h

// -------------------------------------------------------------------------
// shpquads.h  -   this file contains methods for the general serendipity
//                 isoparametric quadrilateral finite element shape.
// -------------------------------------------------------------------------
// Remarks:
// -------------------------------------------------------------------------
// This element is general in the sense that the entire plane isoparametric
// family is represented. Even triangular elements are represented. This is
// indicated by replication of corner nodes.
// -------------------------------------------------------------------------
// The numbering scheme is:
//
//                    s
//                    ^
//                    |    (natural coord. system)
//                    |
//                    -----> r
//
//                                  7
//                        4 +-------+-------+ 3
//                          |               |
//                          |               |
//                        8 +      QUADS    + 6
//                          |               |
//                          |               |
//                        1 +-------+-------+ 2
//                                  5
// -------------------------------------------------------------------------
//  Some of the mid-side nodes indicated above may not exist
//  (indicated by a null - 0 - incidence number), in which case
//  the behavior along that border is linear instead of quadratic.
//  A triangular element can be obtained by collapsing nodes
//  3 and 4, for example.  This is the case when the incidence
//  numbers of these nodes are the same (incidence number of node 7
//  is disregarded in this case).
// -------------------------------------------------------------------------
//
// $Author: evandro $
// $Revision: 1.3 $
// $Date: 1999/04/12 14:58:25 $
// $State: Exp $
//
// -------------------------------------------------------------------------

#ifndef _SHPQUADS_H
#define _SHPQUADS_H

#include "gbldefs.h"
#include "shpplane.h"

// -------------------------------------------------------------------------
// Quads (Finite) Element Shape class:
//
class cShapeQuads : public cPlaneShape
{
 public:
                cShapeQuads       ( void );
  virtual      ~cShapeQuads       ( void );
          void  Connectivity      ( int * );
          int   GetMapOrder       ( void ) { return 2; }
          void  MapFunc           ( sNatCoord *, double * );
          void  ShapeFunc         ( sNatCoord *, double * );
          void  DerivMapRST       ( sNatCoord *, sDerivNat * );
          void  DerivShpRST       ( sNatCoord *, sDerivNat * );
          int   GetEdge           ( int *, eShapeType *, int *, int * );
          int   GetFace           ( int *, eShapeType *, int *, int * );
          void  GetNatCoordMapNode( sNatCoord * );
};

#endif

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