RBGen_ISVDUDV.h

#ifndef RBGEN_ISVDUDV_H
#define RBGEN_ISVDUDV_H

#include "RBGen_IncSVDPOD.h"

//
// computeBasis()
//       |
//   makePass()     ___
//   while () {    /    expand()
//      incStep()  ---- SVD()
//   }             \___ shrink()
//
// makePass(), expand() and shrink() are pure virtual
//
// makePass() is implemented in a base class that decides 
// if a method is Multipass, and if so, in what manner
// makePass() puts the data for the next pass into the proper columns
// of U_, then calls incstep (telling it how many new columns)
//
// incstep calls expand to construct expanded U_ and V_, and B_
// it computes the SVD of B_
// it passes this data to shrink(), which shrink according to the 
// base class.
//
// expand(),shrink() are implemented in a base class that 
// decides the representation: UDV, QRW, QBW
// 
//                                   IncSVDPOD
//                                       |
//      -------------------------------------------------------------------
//      |       |        |           |            |            |          |
//  ISVDUDV  ISVDQRW  ISVDQBW   ISVDMultiCD ISVDMultiSDA ISVDMultiSDB ISVDSingle
//      |       |        |           |            |            |          |
//      ------------------           --------------------------------------
//              \                                       /
//               \                                     /
//                \                                   /
//                 \                                 /
//                  \                               /
//                   \---  Concrete Base Class ----/
//
// Then a concrete base class (one of 3x4==12 varieties) is formed simply through
// inheritence. This is the Template Pattern type of Design Pattern.
//

namespace RBGen {

  class ISVDUDV : public virtual IncSVDPOD {

  public:


    ISVDUDV();

    virtual ~ISVDUDV() {};



    void Initialize( const Teuchos::RCP< Teuchos::ParameterList >& params,
                     const Teuchos::RCP< const Epetra_MultiVector >& init,
                     const Teuchos::RCP< RBGen::FileIOHandler< Epetra_Operator > >& fileio = Teuchos::null );


  protected:

    // private member for performing inc steps
    void expand(const int lup);
    void shrink(const int down, std::vector<double> &S, Epetra_SerialDenseMatrix &U, Epetra_SerialDenseMatrix &V);

    // workspace for U_*U1
    Teuchos::RCP<Epetra_MultiVector> workU_, workV_;
  };

} // end of RBGen namespace

#endif // RBGEN_ISVDUDV_H