Chris@49: // Copyright (C) 2011-2012 Ryan Curtin
Chris@49: //
Chris@49: // This Source Code Form is subject to the terms of the Mozilla Public
Chris@49: // License, v. 2.0. If a copy of the MPL was not distributed with this
Chris@49: // file, You can obtain one at http://mozilla.org/MPL/2.0/.
Chris@49: 
Chris@49: //! \addtogroup SpValProxy
Chris@49: //! @{
Chris@49: 
Chris@49: /**
Chris@49:  * Sparse value proxy class, meant to prevent 0s from being added to sparse
Chris@49:  * matrices.  T1 should be either SpMat or SpSubview, and if it's not, bad news
Chris@49:  * is probably coming.  This class only uses T1::add_element() and
Chris@49:  * T1::delete_element().
Chris@49:  */
Chris@49: template<typename T1>
Chris@49: class SpValProxy
Chris@49:   {
Chris@49:   public:
Chris@49: 
Chris@49:   typedef typename T1::elem_type eT; // Convenience typedef
Chris@49: 
Chris@49:   friend class SpMat<eT>;
Chris@49:   friend class SpSubview<eT>;
Chris@49:   
Chris@49:   /**
Chris@49:    * Create the sparse value proxy.
Chris@49:    * Otherwise, pass a pointer to a reference of the value.
Chris@49:    */
Chris@49:   arma_inline SpValProxy(uword row, uword col, T1& in_parent, eT* in_val_ptr = NULL);
Chris@49:   
Chris@49:   //! For swapping operations.
Chris@49:   arma_inline SpValProxy& operator=(const SpValProxy& rhs);
Chris@49:   template<typename T2>
Chris@49:   arma_inline SpValProxy& operator=(const SpValProxy<T2>& rhs);
Chris@49:   
Chris@49:   //! Overload all of the potential operators.
Chris@49:   
Chris@49:   //! First, the ones that could modify a value.
Chris@49:   arma_inline SpValProxy& operator=(const eT rhs);
Chris@49:   arma_inline SpValProxy& operator+=(const eT rhs);
Chris@49:   arma_inline SpValProxy& operator-=(const eT rhs);
Chris@49:   arma_inline SpValProxy& operator*=(const eT rhs);
Chris@49:   arma_inline SpValProxy& operator/=(const eT rhs);
Chris@49:   
Chris@49:   arma_inline SpValProxy& operator++();
Chris@49:   arma_inline SpValProxy& operator--();
Chris@49:   arma_inline eT operator++(const int);
Chris@49:   arma_inline eT operator--(const int);
Chris@49:   
Chris@49:   //! This will work for any other operations that do not modify a value.
Chris@49:   arma_inline operator eT() const;
Chris@49:   
Chris@49:   
Chris@49:   private:
Chris@49:   
Chris@49:   // Deletes the element if it is zero.  Does not check if val_ptr == NULL!
Chris@49:   arma_inline arma_hot void check_zero();
Chris@49:   
Chris@49:   uword row;
Chris@49:   uword col;
Chris@49:   
Chris@49:   eT* val_ptr;
Chris@49:   
Chris@49:   T1& parent; // We will call this object if we need to insert or delete an element.
Chris@49:   };
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! @}