// ENERGY211/CME211//// sparsemat.h - header file for sparsemat project//#ifndef CLASS_SPARSEMAT#define CLASS_SPARSEMAT#include <map>#include <set>#include <iostream>#include <ostream>#include <stdexcept>	// Need this to use std::runtime_error						// class, for reporting errorstypedef std::map<std::pair<int, int>, double > matrix_map;typedef matrix_map::iterator mat_iter;typedef matrix_map::const_iterator mat_citer;typedef std::map<int, std::set<int> > iset_map;typedef iset_map::iterator iset_iter;typedef iset_map::const_iterator iset_citer;typedef std::set<int>::iterator elt_iter;typedef std::set<int>::const_iterator elt_citer;class SparseMatrix {public:	// Constructor 	SparseMatrix( int rows = 0, int cols = 0 );	// Copy constructor	SparseMatrix( const SparseMatrix& A );	enum ErrorCode {		ERROR_SIZE_MISMATCH = 1,		ERROR_INVALID_INDEX = 2	} ;	~SparseMatrix();	int get_rows() const { return m_rows; }	int get_cols() const { return m_cols; }		void Identity( int rows, int cols = 0 );	SparseMatrix operator+( const SparseMatrix& B ) const;	SparseMatrix operator-() const;	SparseMatrix operator-( const SparseMatrix& B ) const;	SparseMatrix operator*( const SparseMatrix& B ) const;	SparseMatrix operator*( double s ) const;	SparseMatrix operator/( double s ) const;	SparseMatrix Transpose() const;	SparseMatrix& operator=( const SparseMatrix& A );	SparseMatrix& operator+=( const SparseMatrix& A );	SparseMatrix& operator-=( const SparseMatrix& A );	SparseMatrix& operator*=( double s );	SparseMatrix& operator/=( double s );		void Squeeze( double tol = 0.0 );		int nnz() const;		elt_citer get_row_begin( int i ) const;	elt_citer get_row_end( int i ) const;		elt_citer get_col_begin( int i ) const;	elt_citer get_col_end( int i ) const;			double& operator()( int i, int j );	double operator()( int i, int j ) const;	SparseMatrix TriU( int diag = 0 ) const;	SparseMatrix TriL( int diag = 0 ) const;	private:	int m_rows;	int m_cols;	matrix_map m_data;			iset_map m_row_indices;	iset_map m_col_indices;		double Get( int i, int j ) const;	void Set( int i, int j, double x );	void SetSize( int rows, int cols );	// Leave these alone!  They are used for error reporting	static void ReportError( ErrorCode errorcode );	static char *ErrorMessages[];} ;std::ostream& operator<<( std::ostream& os, const SparseMatrix& A );SparseMatrix operator*( double s, const SparseMatrix& A );#endif // CLASS_SPARSEMAT