text: // SPDX-License-Identifier: Apache-2.0
  // 
  // Copyright 2008-2016 Conrad Sanderson (http://conradsanderson.id.au)
  // Copyright 2008-2016 National ICT Australia (NICTA)
  // 
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  // http://www.apache.org/licenses/LICENSE-2.0
  // 
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  // ------------------------------------------------------------------------
  
  
  //! \addtogroup subview_elem2
  //! @{
  
  
  
  template<typename eT, typename T1, typename T2>
  class subview_elem2 : public Base< eT, subview_elem2<eT,T1,T2> >
    {
    public:    
    
    typedef eT                                       elem_type;
    typedef typename get_pod_type<elem_type>::result pod_type;
    
    static constexpr bool is_row  = false;
    static constexpr bool is_col  = false;
    static constexpr bool is_xvec = false;
    
    arma_aligned const Mat<eT>& m;
    
    arma_aligned const Base<uword,T1>& base_ri;
    arma_aligned const Base<uword,T2>& base_ci;
    
    const bool all_rows;
    const bool all_cols;
    
    
    protected:
    
    arma_inline subview_elem2(const Mat<eT>& in_m, const Base<uword,T1>& in_ri, const Base<uword,T2>& in_ci, const bool in_all_rows, const bool in_all_cols);
    
    
    public:
    
    inline ~subview_elem2();
    inline  subview_elem2() = delete;
    
    template<typename op_type>
    inline void inplace_op(const eT val);
    
    template<typename op_type, typename expr>
    inline void inplace_op(const Base<eT,expr>& x);
    
    inline void replace(const eT old_val, const eT new_val);
    
    inline void clean(const pod_type threshold);
    
    inline void clamp(const eT min_val, const eT max_val);
    
    inline void fill(const eT val);
    inline void zeros();
    inline void ones();
    
    inline void operator+= (const eT val);
    inline void operator-= (const eT val);
    inline void operator*= (const eT val);
    inline void operator/= (const eT val);
    
    
    // deliberately returning void
    template<typename T3, typename T4> inline void operator_equ(const subview_elem2<eT,T3,T4>& x);
    template<typename T3, typename T4> inline void operator=   (const subview_elem2<eT,T3,T4>& x);
                                       inline void operator=   (const subview_elem2<eT,T1,T2>& x);
    
    template<typename T3, typename T4> inline void operator+=  (const subview_elem2<eT,T3,T4>& x);
    template<typename T3, typename T4> inline void operator-=  (const subview_elem2<eT,T3,T4>& x);
    template<typename T3, typename T4> inline void operator%=  (const subview_elem2<eT,T3,T4>& x);
    template<typename T3, typename T4> inline void operator/=  (const subview_elem2<eT,T3,T4>& x);
    
    template<typename expr> inline void operator=  (const Base<eT,expr>& x);
    template<typename expr> inline void operator+= (const Base<eT,expr>& x);
    template<typename expr> inline void operator-= (const Base<eT,expr>& x);
    template<typename expr> inline void operator%= (const Base<eT,expr>& x);
    template<typename expr> inline void operator/= (const Base<eT,expr>& x);
    
    template<typename expr> inline void operator=  (const SpBase<eT,expr>& x);
    template<typename expr> inline void operator+= (const SpBase<eT,expr>& x);
    template<typename expr> inline void operator-= (const SpBase<eT,expr>& x);
    template<typename expr> inline void operator%= (const SpBase<eT,expr>& x);
    template<typename expr> inline void operator/= (const SpBase<eT,expr>& x);
    
    inline static void extract(Mat<eT>& out, const subview_elem2& in);
    
    inline static void  plus_inplace(Mat<eT>& out, const subview_elem2& in);
    inline static void minus_inplace(Mat<eT>& out, const subview_elem2& in);
    inline static void schur_inplace(Mat<eT>& out, const subview_elem2& in);
    inline static void   div_inplace(Mat<eT>& out, const subview_elem2& in);
    
    
    friend class Mat<eT>;
    };
  
  
  
  //! @}
  