AbstractLinAlgPack_SparseElement.hpp

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// Moocho: Multi-functional Object-Oriented arCHitecture for Optimization
//                  Copyright (2003) Sandia Corporation
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#ifndef SPARSE_ELEMENT_H
#define SPARSE_ELEMENT_H

#include "AbstractLinAlgPack_Types.hpp"

namespace AbstractLinAlgPack {

template <class T_Index, class T_Value>
class SparseElement {
public:

  typedef T_Value           value_type;
  typedef T_Index           index_type;



  SparseElement()
  {
    idx_pad_.index_  = 0;
    value_           = 0.0;
  }

  SparseElement(index_type index, value_type value)
  {
    idx_pad_.index_ = index;
    value_          = value;
  }
  


  value_type& value()
  {
    return value_;
  }
  const value_type& value() const
  {
    return value_;
  }
  const index_type& index() const
  {
    return idx_pad_.index_;
  }
  void initialize(index_type index, value_type value) {
    idx_pad_.index_ = index;
    value_          = value;
  } 
  void change_index(index_type index)
  {
    idx_pad_.index_ = index;
  }


private:
  union index_and_padding {
    value_type  dummy;     // This is just included for alignment
    index_type index_;   // so that sizeof(this) == 2*sizeof(value_type)
  };
  index_and_padding   idx_pad_;
  value_type        value_;

};  // end class SparseElement

} // end namespace AbstractLinAlgPack 

#endif // SPARSE_ELEMENT_H