text: //=================================================================================================
  /*!
  //  \file blaze/math/expressions/SMatDeclDiagExpr.h
  //  \brief Header file for the sparse matrix diagonal declaration expression
  //
  //  Copyright (C) 2012-2019 Klaus Iglberger - All Rights Reserved
  //
  //  This file is part of the Blaze library. You can redistribute it and/or modify it under
  //  the terms of the New (Revised) BSD License. Redistribution and use in source and binary
  //  forms, with or without modification, are permitted provided that the following conditions
  //  are met:
  //
  //  1. Redistributions of source code must retain the above copyright notice, this list of
  //     conditions and the following disclaimer.
  //  2. Redistributions in binary form must reproduce the above copyright notice, this list
  //     of conditions and the following disclaimer in the documentation and/or other materials
  //     provided with the distribution.
  //  3. Neither the names of the Blaze development group nor the names of its contributors
  //     may be used to endorse or promote products derived from this software without specific
  //     prior written permission.
  //
  //  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
  //  EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  //  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  //  SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  //  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  //  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  //  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  //  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  //  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  //  DAMAGE.
  */
  //=================================================================================================
  
  #ifndef _BLAZE_MATH_EXPRESSIONS_SMATDECLDIAGEXPR_H_
  #define _BLAZE_MATH_EXPRESSIONS_SMATDECLDIAGEXPR_H_
  
  
  //*************************************************************************************************
  // Includes
  //*************************************************************************************************
  
  #include <iterator>
  #include <blaze/math/adaptors/diagonalmatrix/BaseTemplate.h>
  #include <blaze/math/Aliases.h>
  #include <blaze/math/constraints/Diagonal.h>
  #include <blaze/math/constraints/SparseMatrix.h>
  #include <blaze/math/constraints/StorageOrder.h>
  #include <blaze/math/Exception.h>
  #include <blaze/math/expressions/Declaration.h>
  #include <blaze/math/expressions/DeclDiagExpr.h>
  #include <blaze/math/expressions/Forward.h>
  #include <blaze/math/expressions/SparseMatrix.h>
  #include <blaze/math/sparse/Forward.h>
  #include <blaze/math/traits/DeclDiagTrait.h>
  #include <blaze/math/typetraits/IsDiagonal.h>
  #include <blaze/math/typetraits/IsExpression.h>
  #include <blaze/math/typetraits/IsLower.h>
  #include <blaze/math/typetraits/IsSymmetric.h>
  #include <blaze/math/typetraits/IsUpper.h>
  #include <blaze/math/typetraits/RequiresEvaluation.h>
  #include <blaze/util/Assert.h>
  #include <blaze/util/DisableIf.h>
  #include <blaze/util/EnableIf.h>
  #include <blaze/util/FunctionTrace.h>
  #include <blaze/util/IntegralConstant.h>
  #include <blaze/util/InvalidType.h>
  #include <blaze/util/mpl/If.h>
  #include <blaze/util/Types.h>
  #include <blaze/util/typetraits/GetMemberType.h>
  
  
  namespace blaze {
  
  //=================================================================================================
  //
  //  CLASS SMATDECLHERMEXPR
  //
  //=================================================================================================
  
  //*************************************************************************************************
  /*!\brief Expression object for the explicit diagonal declaration of sparse matrices.
  // \ingroup sparse_matrix_expression
  //
  // The SMatDeclDiagExpr class represents the compile time expression for the explicit diagonal
  // declaration of a sparse matrix.
  */
  template< typename MT  // Type of the sparse matrix
          , bool SO >    // Storage order
  class SMatDeclDiagExpr
     : public DeclDiagExpr< SparseMatrix< SMatDeclDiagExpr<MT,SO>, SO > >
     , public Declaration<MT>
  {
   private:
     //**Type definitions****************************************************************************
     using RT = ResultType_t<MT>;  //!< Result type of the sparse matrix expression.
  
     //! Definition of the GetConstIterator type trait.
     BLAZE_CREATE_GET_TYPE_MEMBER_TYPE_TRAIT( GetConstIterator, ConstIterator, INVALID_TYPE );
     //**********************************************************************************************
  
     //**Serial evaluation strategy******************************************************************
     //! Compilation switch for the serial evaluation strategy of the diagonal declaration expression.
     /*! The \a useAssign compile time constant expression represents a compilation switch for
         the serial evaluation strategy of the diagonal declaration expression. In case the given
         sparse matrix expression of type \a MT requires an intermediate evaluation, \a useAssign
         will be set to 1 and the diagonal declaration expression will be evaluated via the
         \a assign function family. Otherwise \a useAssign will be set to 0 and the expression
         will be evaluated via the subscript operator. */
     static constexpr bool useAssign = RequiresEvaluation_v<MT>;
  
     /*! \cond BLAZE_INTERNAL */
     //! Helper variable template for the explicit application of the SFINAE principle.
     template< typename MT2 >
     static constexpr bool UseAssign_v = useAssign;
     /*! \endcond */
     //**********************************************************************************************
  
     //**Parallel evaluation strategy****************************************************************
     /*! \cond BLAZE_INTERNAL */
     //! Helper variable template for the explicit application of the SFINAE principle.
     /*! This variable template is a helper for the selection of the parallel evaluation strategy.
         In case the target matrix is SMP assignable and the sparse matrix operand requires an
         intermediate evaluation, the variable is set to 1 and the expression specific evaluation
         strategy is selected. Otherwise the variable is set to 0 and the default strategy is
         chosen. */
     template< typename MT2 >
     static constexpr bool UseSMPAssign_v = ( MT2::smpAssignable && useAssign );
     /*! \endcond */
     //**********************************************************************************************
  
   public:
     //**Type definitions****************************************************************************
     using This          = SMatDeclDiagExpr<MT,SO>;      //!< Type of this SMatDeclDiagExpr instance.
     using BaseType      = SparseMatrix<This,SO>;        //!< Base type of this SMatDeclDiagExpr instance.
     using ResultType    = DeclDiagTrait_t<RT>;          //!< Result type for expression template evaluations.
     using OppositeType  = OppositeType_t<ResultType>;   //!< Result type with opposite storage order for expression template evaluations.
     using TransposeType = TransposeType_t<ResultType>;  //!< Transpose type for expression template evaluations.
     using ElementType   = ElementType_t<MT>;            //!< Resulting element type.
     using ReturnType    = ReturnType_t<MT>;             //!< Return type for expression template evaluations.
  
     //! Data type for composite expression templates.
     using CompositeType = If_t< RequiresEvaluation_v<MT>, const ResultType, const SMatDeclDiagExpr& >;
  
     //! Iterator over the elements of the dense matrix.
     using ConstIterator = GetConstIterator_t<MT>;
  
     //! Composite data type of the sparse matrix expression.
     using Operand = If_t< IsExpression_v<MT>, const MT, const MT& >;
     //**********************************************************************************************
  
     //**Compilation flags***************************************************************************
     //! Compilation switch for the expression template assignment strategy.
     static constexpr bool smpAssignable = MT::smpAssignable;
     //**********************************************************************************************
  
     //**Constructor*********************************************************************************
     /*!\brief Constructor for the SMatDeclDiagExpr class.
     //
     // \param sm The sparse matrix operand of the decldiag expression.
     */
     explicit inline SMatDeclDiagExpr( const MT& sm ) noexcept
        : sm_( sm )  // Sparse matrix of the decldiag expression
     {
        BLAZE_INTERNAL_ASSERT( isSquare( ~sm ), "Non-square matrix detected" );
     }
     //**********************************************************************************************
  
     //**Access operator*****************************************************************************
     /*!\brief 2D-access to the matrix elements.
     //
     // \param i Access index for the row. The index has to be in the range \f$[0..M-1]\f$.
     // \param j Access index for the column. The index has to be in the range \f$[0..N-1]\f$.
     // \return The resulting value.
     */
     inline ReturnType operator()( size_t i, size_t j ) const {
        BLAZE_INTERNAL_ASSERT( i < sm_.rows()   , "Invalid row access index"    );
        BLAZE_INTERNAL_ASSERT( j < sm_.columns(), "Invalid column access index" );
        return sm_(i,j);
     }
     //**********************************************************************************************
  
     //**At function*********************************************************************************
     /*!\brief Checked access to the matrix elements.
     //
     // \param i Access index for the row. The index has to be in the range \f$[0..M-1]\f$.
     // \param j Access index for the column. The index has to be in the range \f$[0..N-1]\f$.
     // \return The resulting value.
     // \exception std::out_of_range Invalid matrix access index.
     */
     inline ReturnType at( size_t i, size_t j ) const {
        if( i >= sm_.rows() ) {
           BLAZE_THROW_OUT_OF_RANGE( "Invalid row access index" );
        }
        if( j >= sm_.columns() ) {
           BLAZE_THROW_OUT_OF_RANGE( "Invalid column access index" );
        }
        return (*this)(i,j);
     }
     //**********************************************************************************************
  
     //**Begin function******************************************************************************
     /*!\brief Returns an iterator to the first non-zero element of row \a i.
     //
     // \param i The row index.
     // \return Iterator to the first non-zero element of row \a i.
     */
     inline ConstIterator begin( size_t i ) const {
        return ConstIterator( sm_.begin(i) );
     }
     //**********************************************************************************************
  
     //**End function********************************************************************************
     /*!\brief Returns an iterator just past the last non-zero element of row \a i.
     //
     // \param i The row index.
     // \return Iterator just past the last non-zero element of row \a i.
     */
     inline ConstIterator end( size_t i ) const {
        return ConstIterator( sm_.end(i) );
     }
     //**********************************************************************************************
  
     //**Rows function*******************************************************************************
     /*!\brief Returns the current number of rows of the matrix.
     //
     // \return The number of rows of the matrix.
     */
     inline size_t rows() const noexcept {
        return sm_.rows();
     }
     //**********************************************************************************************
  
     //**Columns function****************************************************************************
     /*!\brief Returns the current number of columns of the matrix.
     //
     // \return The number of columns of the matrix.
     */
     inline size_t columns() const noexcept {
        return sm_.columns();
     }
     //**********************************************************************************************
  
     //**NonZeros function***************************************************************************
     /*!\brief Returns the number of non-zero elements in the sparse matrix.
     //
     // \return The number of non-zero elements in the sparse matrix.
     */
     inline size_t nonZeros() const {
        return sm_.nonZeros();
     }
     //**********************************************************************************************
  
     //**NonZeros function***************************************************************************
     /*!\brief Returns the number of non-zero elements in the specified row.
     //
     // \param i The index of the row.
     // \return The number of non-zero elements of row \a i.
     */
     inline size_t nonZeros( size_t i ) const {
        return sm_.nonZeros(i);
     }
     //**********************************************************************************************
  
     //**Operand access******************************************************************************
     /*!\brief Returns the sparse matrix operand.
     //
     // \return The sparse matrix operand.
     */
     inline Operand operand() const noexcept {
        return sm_;
     }
     //**********************************************************************************************
  
     //**********************************************************************************************
     /*!\brief Returns whether the expression can alias with the given address \a alias.
     //
     // \param alias The alias to be checked.
     // \return \a true in case the expression can alias, \a false otherwise.
     */
     template< typename T >
     inline bool canAlias( const T* alias ) const noexcept {
        return sm_.canAlias( alias );
     }
     //**********************************************************************************************
  
     //**********************************************************************************************
     /*!\brief Returns whether the expression is aliased with the given address \a alias.
     //
     // \param alias The alias to be checked.
     // \return \a true in case an alias effect is detected, \a false otherwise.
     */
     template< typename T >
     inline bool isAliased( const T* alias ) const noexcept {
        return sm_.isAliased( alias );
     }
     //**********************************************************************************************
  
     //**********************************************************************************************
     /*!\brief Returns whether the expression can be used in SMP assignments.
     //
     // \return \a true in case the expression can be used in SMP assignments, \a false if not.
     */
     inline bool canSMPAssign() const noexcept {
        return sm_.canSMPAssign();
     }
     //**********************************************************************************************
  
   private:
     //**Member variables****************************************************************************
     Operand sm_;  //!< Sparse matrix of the decldiag expression.
     //**********************************************************************************************
  
     //**Assignment to dense matrices****************************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Assignment of a sparse matrix decldiag expression to a dense matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression to be assigned.
     // \return void
     //
     // This function implements the performance optimized assignment of a sparse matrix decldiag
     // expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto assign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        assign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Assignment to sparse matrices***************************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Assignment of a sparse matrix decldiag expression to a sparse matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression to be assigned.
     // \return void
     //
     // This function implements the performance optimized assignment of a sparse matrix decldiag
     // expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto assign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        assign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Addition assignment to dense matrices*******************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Addition assignment of a sparse matrix decldiag expression to a dense matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression to be added.
     // \return void
     //
     // This function implements the performance optimized addition assignment of a sparse matrix
     // decldiag expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto addAssign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        addAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Addition assignment to sparse matrices******************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Addition assignment of a sparse matrix decldiag expression to a sparse matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression to be added.
     // \return void
     //
     // This function implements the performance optimized addition assignment of a sparse matrix
     // decldiag expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto addAssign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        addAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Subtraction assignment to dense matrices****************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Subtraction assignment of a sparse matrix decldiag expression to a dense matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression to be subtracted.
     // \return void
     //
     // This function implements the performance optimized subtraction assignment of a sparse
     // matrix decldiag expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto subAssign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        subAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Subtraction assignment to sparse matrices***************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Subtraction assignment of a sparse matrix decldiag expression to a sparse matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression to be subtracted.
     // \return void
     //
     // This function implements the performance optimized subtraction assignment of a sparse
     // matrix decldiag expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto subAssign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        subAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Schur product assignment to dense matrices**************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Schur product assignment of a sparse matrix decldiag expression to a dense matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression for the Schur product.
     // \return void
     //
     // This function implements the performance optimized Schur product assignment of a sparse
     // matrix decldiag expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto schurAssign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        schurAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Schur product assignment to sparse matrices*************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Schur product assignment of a sparse matrix decldiag expression to a sparse matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression for the Schur product.
     // \return void
     //
     // This function implements the performance optimized Schur product assignment of a sparse
     // matrix decldiag expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto schurAssign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        schurAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Multiplication assignment to dense matrices*************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Multiplication assignment of a sparse matrix decldiag expression to a dense matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression to be multiplied.
     // \return void
     //
     // This function implements the performance optimized multiplication assignment of a sparse
     // matrix decldiag expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto multAssign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        multAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Multiplication assignment to sparse matrices************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief Multiplication assignment of a sparse matrix decldiag expression to a sparse matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression to be multiplied.
     // \return void
     //
     // This function implements the performance optimized multiplication assignment of a sparse
     // matrix decldiag expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto multAssign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        multAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP assignment to dense matrices************************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP assignment of a sparse matrix decldiag expression to a dense matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression to be assigned.
     // \return void
     //
     // This function implements the performance optimized SMP assignment of a sparse matrix
     // decldiag expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto smpAssign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP assignment to sparse matrices***********************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP assignment of a sparse matrix decldiag expression to a sparse matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression to be assigned.
     // \return void
     //
     // This function implements the performance optimized SMP assignment of a sparse matrix
     // decldiag expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto smpAssign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP addition assignment to dense matrices***************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP addition assignment of a sparse matrix decldiag expression to a dense matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression to be added.
     // \return void
     //
     // This function implements the performance optimized SMP addition assignment of a sparse
     // matrix decldiag expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto smpAddAssign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpAddAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP addition assignment to sparse matrices**************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP addition assignment of a sparse matrix decldiag expression to a sparse matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression to be added.
     // \return void
     //
     // This function implements the performance optimized SMP addition assignment of a sparse
     // matrix decldiag expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto smpAddAssign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpAddAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP subtraction assignment to dense matrices************************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP subtraction assignment of a sparse matrix decldiag expression to a dense matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression to be subtracted.
     // \return void
     //
     // This function implements the performance optimized SMP subtraction assignment of a sparse
     // matrix decldiag expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto smpSubAssign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpSubAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP subtraction assignment to sparse matrices***********************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP subtraction assignment of a sparse matrix decldiag expression to a sparse matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression to be subtracted.
     // \return void
     //
     // This function implements the performance optimized SMP subtraction assignment of a sparse
     // matrix decldiag expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto smpSubAssign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpSubAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP Schur product assignment to dense matrices**********************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP Schur product assignment of a sparse matrix decldiag expression to a dense matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression for the Schur product.
     // \return void
     //
     // This function implements the performance optimized SMP Schur product assignment of a sparse
     // matrix decldiag expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto smpSchurAssign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpSchurAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP Schur product assignment to sparse matrices*********************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP Schur product assignment of a sparse matrix decldiag expression to a sparse matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression for the Schur product.
     // \return void
     //
     // This function implements the performance optimized SMP Schur product assignment of a sparse
     // matrix decldiag expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto smpSchurAssign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpSchurAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP multiplication assignment to dense matrices*********************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP multiplication assignment of a sparse matrix decldiag expression to a dense
     //        matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side dense matrix.
     // \param rhs The right-hand side decldiag expression to be multiplied.
     // \return void
     //
     // This function implements the performance optimized SMP multiplication assignment of a
     // sparse matrix decldiag expression to a dense matrix.
     */
     template< typename MT2  // Type of the target dense matrix
             , bool SO2 >    // Storage order of the target dense matrix
     friend inline auto smpMultAssign( DenseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpMultAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**SMP multiplication assignment to sparse matrices********************************************
     /*! \cond BLAZE_INTERNAL */
     /*!\brief SMP multiplication assignment of a sparse matrix decldiag expression to a sparse
     //        matrix.
     // \ingroup sparse_matrix
     //
     // \param lhs The target left-hand side sparse matrix.
     // \param rhs The right-hand side decldiag expression to be multiplied.
     // \return void
     //
     // This function implements the performance optimized SMP multiplication assignment of a
     // sparse matrix decldiag expression to a sparse matrix.
     */
     template< typename MT2  // Type of the target sparse matrix
             , bool SO2 >    // Storage order of the target sparse matrix
     friend inline auto smpMultAssign( SparseMatrix<MT2,SO2>& lhs, const SMatDeclDiagExpr& rhs )
        -> EnableIf_t< UseSMPAssign_v<MT2> >
     {
        BLAZE_FUNCTION_TRACE;
  
        BLAZE_INTERNAL_ASSERT( (~lhs).rows()    == rhs.rows()   , "Invalid number of rows"    );
        BLAZE_INTERNAL_ASSERT( (~lhs).columns() == rhs.columns(), "Invalid number of columns" );
  
        smpMultAssign( ~lhs, rhs.sm_ );
     }
     /*! \endcond */
     //**********************************************************************************************
  
     //**Compile time checks*************************************************************************
     /*! \cond BLAZE_INTERNAL */
     BLAZE_CONSTRAINT_MUST_BE_SPARSE_MATRIX_TYPE( MT );
     BLAZE_CONSTRAINT_MUST_BE_MATRIX_WITH_STORAGE_ORDER( MT, SO );
     BLAZE_CONSTRAINT_MUST_NOT_BE_DIAGONAL_MATRIX_TYPE( MT );
     /*! \endcond */
     //**********************************************************************************************
  };
  //*************************************************************************************************
  
  
  
  
  //=================================================================================================
  //
  //  GLOBAL FUNCTIONS
  //
  //=================================================================================================
  
  //*************************************************************************************************
  /*! \cond BLAZE_INTERNAL */
  /*!\brief Declares the given sparse matrix expression \a sm as diagonal.
  // \ingroup sparse_matrix
  //
  // \param sm The input matrix.
  // \return The redeclared sparse matrix.
  //
  // This function declares the given sparse matrix expression \a sm as diagonal. The function
  // returns an expression representing the operation.
  */
  template< typename MT  // Type of the sparse matrix
          , bool SO      // Storage order
          , DisableIf_t< IsDiagonal_v<MT> >* = nullptr >
  inline const SMatDeclDiagExpr<MT,SO> decldiag_backend( const SparseMatrix<MT,SO>& sm )
  {
     BLAZE_FUNCTION_TRACE;
  
     BLAZE_INTERNAL_ASSERT( isSquare( ~sm ), "Non-square matrix detected" );
  
     return SMatDeclDiagExpr<MT,SO>( ~sm );
  }
  /*! \endcond */
  //*************************************************************************************************
  
  
  //*************************************************************************************************
  /*! \cond BLAZE_INTERNAL */
  /*!\brief Redeclares the given diagonal sparse matrix expression \a sm as diagonal.
  // \ingroup sparse_matrix
  //
  // \param sm The input matrix.
  // \return The redeclared sparse matrix.
  //
  // This function redeclares the given diagonal sparse matrix expression \a sm as diagonal.
  // The function returns a reference to the already diagonal matrix expression.
  */
  template< typename MT  // Type of the sparse matrix
          , bool SO      // Storage order
          , EnableIf_t< IsDiagonal_v<MT> >* = nullptr >
  inline const MT& decldiag_backend( const SparseMatrix<MT,SO>& sm )
  {
     BLAZE_FUNCTION_TRACE;
  
     BLAZE_INTERNAL_ASSERT( isSquare( ~sm ), "Non-square matrix detected" );
  
     return ~sm;
  }
  /*! \endcond */
  //*************************************************************************************************
  
  
  //*************************************************************************************************
  /*!\brief Declares the given sparse matrix expression \a sm as diagonal.
  // \ingroup sparse_matrix
  //
  // \param sm The input matrix.
  // \return The redeclared sparse matrix.
  // \exception std::invalid_argument Invalid diagonal matrix specification.
  //
  // The \a decldiag function declares the given sparse matrix expression \a sm as diagonal. In
  // case the given matrix is not a square matrix, a \a std::invalid_argument exception is thrown.\n
  // The following example demonstrates the use of the \a decldiag function:
  
     \code
     blaze::CompressedMatrix<double> A, B;
     // ... Resizing and initialization
     B = decldiag( A );
     \endcode
  */
  template< typename MT  // Type of the sparse matrix
          , bool SO >    // Storage order
  inline decltype(auto) decldiag( const SparseMatrix<MT,SO>& sm )
  {
     BLAZE_FUNCTION_TRACE;
  
     if( !isSquare( ~sm ) ) {
        BLAZE_THROW_INVALID_ARGUMENT( "Invalid diagonal matrix specification" );
     }
  
     return decldiag_backend( ~sm );
  }
  //*************************************************************************************************
  
  
  
  
  //=================================================================================================
  //
  //  GLOBAL RESTRUCTURING FUNCTIONS
  //
  //=================================================================================================
  
  //*************************************************************************************************
  /*! \cond BLAZE_INTERNAL */
  /*!\brief Declares the given non-diagonal sparse matrix-scalar multiplication expression as diagonal.
  // \ingroup sparse_matrix
  //
  // \param sm The input sparse matrix-scalar multiplication expression.
  // \return The redeclared expression.
  // \exception std::invalid_argument Invalid diagonal matrix specification.
  //
  // This function implements the application of the decldiag() operation on a sparse matrix-
  // scalar multiplication. It restructures the expression \f$ A=decldiag(B*s1) \f$ to the
  // expression \f$ A=decldiag(B)*s1 \f$. In case the given matrix is not a square matrix,
  // a \a std::invalid_argument exception is thrown.
  */
  template< typename MT  // Type of the left-hand side sparse matrix
          , typename ST  // Type of the right-hand side scalar value
          , bool SO      // Storage order
          , DisableIf_t< IsDiagonal_v<MT> >* = nullptr >
  inline decltype(auto) decldiag( const SMatScalarMultExpr<MT,ST,SO>& sm )
  {
     BLAZE_FUNCTION_TRACE;
  
     if( !isSquare( ~sm ) ) {
        BLAZE_THROW_INVALID_ARGUMENT( "Invalid diagonal matrix specification" );
     }
  
     return decldiag( sm.leftOperand() ) * sm.rightOperand();
  }
  /*! \endcond */
  //*************************************************************************************************
  
  
  
  
  //=================================================================================================
  //
  //  ISSYMMETRIC SPECIALIZATIONS
  //
  //=================================================================================================
  
  //*************************************************************************************************
  /*! \cond BLAZE_INTERNAL */
  template< typename MT, bool SO >
  struct IsSymmetric< SMatDeclDiagExpr<MT,SO> >
     : public TrueType
  {};
  /*! \endcond */
  //*************************************************************************************************
  
  
  
  
  //=================================================================================================
  //
  //  ISLOWER SPECIALIZATIONS
  //
  //=================================================================================================
  
  //*************************************************************************************************
  /*! \cond BLAZE_INTERNAL */
  template< typename MT, bool SO >
  struct IsLower< SMatDeclDiagExpr<MT,SO> >
     : public TrueType
  {};
  /*! \endcond */
  //*************************************************************************************************
  
  
  
  
  //=================================================================================================
  //
  //  ISUPPER SPECIALIZATIONS
  //
  //=================================================================================================
  
  //*************************************************************************************************
  /*! \cond BLAZE_INTERNAL */
  template< typename MT, bool SO >
  struct IsUpper< SMatDeclDiagExpr<MT,SO> >
     : public TrueType
  {};
  /*! \endcond */
  //*************************************************************************************************
  
  } // namespace blaze
  
  #endif
  