Thyra_DetachedVectorView.hpp

// @HEADER
// *****************************************************************************
//    Thyra: Interfaces and Support for Abstract Numerical Algorithms
//
// Copyright 2004 NTESS and the Thyra contributors.
// SPDX-License-Identifier: BSD-3-Clause
// *****************************************************************************
// @HEADER

#include "Thyra_VectorBase.hpp"

#ifndef THYRA_EXPLICIT_VECTOR_VIEW_HPP
#define THYRA_EXPLICIT_VECTOR_VIEW_HPP


namespace Thyra {


template<class Scalar>
class ConstDetachedVectorView {
public:

  ConstDetachedVectorView(
    const Teuchos::RCP<const VectorBase<Scalar> > &v
    ,const Range1D &rng = Range1D(), const bool forceUnitStride = false
    )
    {
      this->initialize(v,rng,forceUnitStride);
    }

  ConstDetachedVectorView( const VectorBase<Scalar>& v,
    const Range1D &rng = Range1D(), const bool forceUnitStride = false )
    {
      this->initialize(Teuchos::rcp(&v,false),rng,forceUnitStride);
    }

  ~ConstDetachedVectorView()
    {
      if( sv_s_.stride() != sv_.stride() )
        delete [] const_cast<Scalar*>(sv_.values().get());
      v_->releaseDetachedView(&sv_s_);
    }

  const RTOpPack::ConstSubVectorView<Scalar>& sv() const { return sv_; }

  Teuchos_Ordinal globalOffset() const { return sv_.globalOffset(); }

  Teuchos_Ordinal subDim() const { return sv_.subDim(); }

  const Scalar* values() const { return sv_.values().get(); }

  ptrdiff_t stride() const { return sv_.stride(); }

  const Scalar& operator[](Teuchos_Ordinal i) const { return sv_[i]; }

  const Scalar& operator()(Teuchos_Ordinal i) const { return sv_(i); }

private:

  Teuchos::RCP<const VectorBase<Scalar> > v_;
  RTOpPack::ConstSubVectorView<Scalar>  sv_s_;
  RTOpPack::ConstSubVectorView<Scalar>  sv_;

  void initialize(
    const Teuchos::RCP<const VectorBase<Scalar> > &v,
    const Range1D &rng, const bool forceUnitStride
    )
    {
      v_ = v;
      v_->acquireDetachedView(rng,&sv_s_);
      if( forceUnitStride && sv_s_.stride() != 1 ) {
        TEUCHOS_TEST_FOR_EXCEPT_MSG(true, "I don't think non-unit stride has ever been tested!");
        //const ArrayRCP<Scalar> values = Teuchos::arcp(sv_s_.subDim());
        //Teuchos_Ordinal i; const Scalar *sv_v;
        //for( sv_v = sv_s_.values().get(), i=0; i < sv_s_.subDim(); ++i, sv_v += sv_s_.stride() )
        //  values[i] = *sv_v;
        //sv_.initialize(sv_s_.globalOffset(),sv_s_.subDim(),values,1);
      }
      else {
        sv_ = sv_s_;
      }
    }
  // Not defined and not to be called
  ConstDetachedVectorView();
  ConstDetachedVectorView(const ConstDetachedVectorView<Scalar>&);
  ConstDetachedVectorView<Scalar>& operator==(const ConstDetachedVectorView<Scalar>&);
};

 
template<class Scalar>
class DetachedVectorView {
public:

  DetachedVectorView(
    const Teuchos::RCP<VectorBase<Scalar> > &v
    ,const Range1D &rng = Range1D(), const bool forceUnitStride = false
    )
    {
      this->initialize(v,rng,forceUnitStride);
    }

  DetachedVectorView( VectorBase<Scalar>& v, const Range1D &rng = Range1D(), const bool forceUnitStride = false )
    {
      this->initialize(Teuchos::rcp(&v,false),rng,forceUnitStride);
    }

  ~DetachedVectorView()
    {
      if( sv_s_.stride() != sv_.stride() ) {
        Teuchos::TestForTermination_terminate("I don't think non-unit stride has ever been tested!");
        //Teuchos_Ordinal i; Scalar *sv_v; const Scalar *values;
        //for (
        //  sv_v = sv_s_.values().get(), values = sv_.values().get(), i=0;
        //  i < sv_s_.subDim();
        //  ++i, sv_v += sv_s_.stride()
        //  )
        //{
        //  *sv_v = *values++;
        //}
        //delete [] sv_.values().get();
      }
      v_->commitDetachedView(&sv_s_);
    }

  const RTOpPack::SubVectorView<Scalar>& sv() const { return sv_; }

  Teuchos_Ordinal globalOffset() const { return sv_.globalOffset(); }

  Teuchos_Ordinal subDim() const { return sv_.subDim(); }

  Scalar* values() const { return sv_.values().get(); }

  ptrdiff_t stride() const { return sv_.stride(); }

  Scalar& operator[](Teuchos_Ordinal i) const { return sv_[i]; }

  Scalar& operator()(Teuchos_Ordinal i) const { return sv_(i); }

private:

  Teuchos::RCP<VectorBase<Scalar> > v_;
  RTOpPack::SubVectorView<Scalar>  sv_s_;
  RTOpPack::SubVectorView<Scalar>  sv_;

  void initialize(
    const Teuchos::RCP<VectorBase<Scalar> > &v
    ,const Range1D &rng, const bool forceUnitStride
    )
    {
      v_ = v;
      v_->acquireDetachedView(rng,&sv_s_);
      if( forceUnitStride && sv_s_.stride() != 1 ) {
        TEUCHOS_TEST_FOR_EXCEPT_MSG(true, "I don't think non-unit stride has ever been tested!");
        //Scalar *values = new Scalar[sv_s_.subDim()];
        //Teuchos_Ordinal i; const Scalar *sv_v;
        //for( sv_v = sv_s_.values().get(), i=0; i < sv_s_.subDim(); ++i, sv_v += sv_s_.stride() )
        //  values[i] = *sv_v;
        //sv_.initialize(sv_s_.globalOffset(),sv_s_.subDim(),values,1);
      }
      else {
        sv_ = sv_s_;
      }
    }

  // Not defined and not to be called
  DetachedVectorView();
  DetachedVectorView(const DetachedVectorView<Scalar>&);
  DetachedVectorView<Scalar>& operator==(const DetachedVectorView<Scalar>&);

};


} // namespace Thyra


#endif // THYRA_EXPLICIT_VECTOR_VIEW_HPP