/** 
 * @file GMSparse2.h
 * @brief Sparse Matrix depends on SparseVectors
 * @author Björn Fröhlich
 * @date 05/14/2009

 */
#ifndef GMSPARSE2INCLUDE
#define GMSPARSE2INCLUDE

#include "core/vector/VectorT.h"
#include "core/vector/MatrixT.h"

#include "vislearning/math/algebra/GenericMatrix.h"
  
namespace OBJREC {

class GMSparse2 : public GenericMatrix
{
	protected:
		//! the sparse matrix
		std::vector<NICE::SparseVector*> A;
		
		//! count of rows
		uint m_rows;
		
		//! count of columns
		uint m_cols;
		
		//! are the vectors new ones or came they from somewhere else
		bool newvectors;
		
	public:
		/**
		 * simple constructor -> does nothing
		 */
		GMSparse2(){resize(0,0);};
		
		/**
		 * constructor which set the rows and cols of the SparseMatrix
		 * @param _rows 
		 * @param _cols 
		 */
		GMSparse2 ( uint _rows, uint _cols );
		
		/**
		 * converts an ICE::Matrix to a sparse matrix
		 * @param A input ICE::Matrix
		 * @param epsilon tolerance value
		 */
		GMSparse2 ( const NICE::Matrix & iceA, double epsilon = 1e-9 );

		/**
		 * simple destructor
		 */
		~GMSparse2();
		
		/**
		 * resize the matrix
		 * @param _rows new count of rows
		 * @param _cols new count of cols
		 */
		void resize( int _rows, int _cols);
		
		/**
		 * clean up
		 */
		void clear();
		
		/** get the number of rows in A */
		uint rows() const { return m_rows; };

		/** get the number of columns in A */
		uint cols() const { return m_cols; };

		/** multiply with a vector: A*x = y */
		void multiply ( NICE::Vector & y, const NICE::Vector & x ) const;
		
		/**
		 * return the i-th row
		 * @param i 
		 * @return SparseVector at row i
		 */
		NICE::SparseVector & operator[](int i) const;
		
		/**
		 * restore the information of the sparse matrix
		 * @param is inputstream
		 * @param format 
		 */
		void restore (std::istream & is, int format = 0);
		
		/**
		 * store the information of the sparse matrix
		 * @param os outputstream
		 * @param format 
		 */
		void store (std::ostream & os, int format = 0) const;
		
		
		/**
		 * Should the data be deleted when the destructor is called
		 * @param del 
		 */
		void setDel(bool del = true);
		
		/**
		 * add a new row 
		 * @param x ICE::Vector
		 */
		void addRow(const NICE::Vector &x);
		
		/**
		 * add a new row
		 * @param x SparseVector
		 */
		void addRow(NICE::SparseVector *x);
		
		/**
		 * matrixmultiplication x*y = out
		 * @param y input
		 * @param out output
		 * @param transpx use the transpose of x 
		 * @param transpy use the transpose of y
		 * @return z
		 */
		void mult(GMSparse2 &y, GMSparse2 & out, bool transpx = false, bool transpy = false);
		
		/**
		 * matrixmultiplication x*y = out
		 * @param y input Sparse Vector
		 * @param out output
		 * @param transpx use the transpose of x 
		 * @param transpy use the transpose of y
		 * @return z
		 */
		void mult(NICE::SparseVector &y, GMSparse2 & out, bool transpx = false, bool transpy = false);
		
		/**
		 * same like mult, but faster when y ist very sparse and slower if not
		 * @param y input
		 * @param out output
		 * @param transpx use the transpose of x 
		 * @param transpy use the transpose of y
		 * @return z
		 */
		void mult2(GMSparse2 &y, GMSparse2 & out, bool transpx = false, bool transpy = false);
};

} // namespace

#endif