Add member functions to MatDense: eq_cols, eq_rows, sum_col, sum_row,...

Add member functions to MatDense: eq_cols, eq_rows, sum_col, sum_row, best_low_rank, row_nonzero_inds, col_nonzero_inds, submatrix.

NOTE: it needs eigen >= 3.4 to compile (slicing support is needed by submatrix()).

src/faust_linear_operator/CPU/faust_MatDense.h

@@ -384,6 +384,14 @@ namespace Faust
 			MatDense<FPP,Cpu>* get_cols(faust_unsigned_int start_col_id, faust_unsigned_int num_cols) const;
 			MatDense<FPP,Cpu>* get_cols(faust_unsigned_int* col_ids, faust_unsigned_int n) const;
 			MatDense<FPP,Cpu>* get_cols(std::vector<int> col_ids) const;
+			/** \brief Returns true if this[:,id_this] == other[:, id_other] at the specified precision. */
+			bool eq_cols(const MatDense<FPP, Cpu> & other, faust_unsigned_int id_this, faust_unsigned_int id_other, const Real<FPP>& precision) const;
+			/** \brief Returns true if this[id_this, :] == other[id_other, :] at the specified precision. */
+			bool eq_rows(const MatDense<FPP, Cpu> & other, faust_unsigned_int id_this, faust_unsigned_int id_other, const Real<FPP>& precision) const;
+			/** \brief Returns the sum of the column of index id. */
+			FPP sum_col(faust_unsigned_int id) const;
+			/** \brief Returns the sum of the row of index id. */
+			FPP sum_row(faust_unsigned_int id) const;
 			void delete_col(int offset);
 			void delete_row(int offset);
 
@@ -468,6 +476,22 @@ namespace Faust
 			 */
 			std::list<std::pair<int,int>> nonzeros_indices() const;
 
+			/**
+			 * \brief Returns the best low rank approximation this = bestX * bestY using the svd.
+			 */
+			void best_low_rank(const int &r, MatDense<FPP,Cpu> &bestX, MatDense<FPP, Cpu> &bestY) const;
+			/**
+			 * Returns the vector of the indices of the nonzeros of the row of index row_id.
+			 */
+			std::vector<int> row_nonzero_inds(faust_unsigned_int row_id) const;
+			/**
+			 * Returns the vector of the indices of the nonzeros of the column of index col_id.
+			 */
+			std::vector<int> col_nonzero_inds(faust_unsigned_int col_id) const;
+			/**
+			 * Returns in submat the submatrix defined by the row indices row_ids and the column indices col_ids.
+			 */
+			void submatrix(const std::vector<int> &row_ids, const std::vector<int> &col_ids, MatDense<FPP, Cpu> & submat) const;
 			private:
 			Eigen::Matrix<FPP, Eigen::Dynamic, Eigen::Dynamic> mat;
 			bool isZeros;

src/faust_linear_operator/CPU/faust_MatDense.hpp

@@ -53,7 +53,7 @@
 #include "faust_exception.h"
 #include "faust_constant.h"
 #include <cassert>
-
+#include <Eigen/SVD>
 
 namespace Faust
 {
@@ -202,7 +202,7 @@ namespace Faust
 			std::list<std::pair<int,int>> nz_inds;
 			if(this->is_identity)
 #ifdef _MSC_VER
-				for(int i=0;i<min(this->dim1, this->dim2);i++) // VS14 strange issue with std::min //C2589 or C2059
+				for(int i=0;i<min(this->dim1, this->dim2);i++) // VS14 strange issue with std::min //C2589 or C2059 // TODO/ fix rather with -DNOMINMAX
 #else
 					for(int i=0;i<std::min(this->dim1, this->dim2);i++)
 #endif
@@ -1221,6 +1221,88 @@ MatDense<FPP,Cpu>* MatDense<FPP,Cpu>::get_rows(faust_unsigned_int* row_ids, faus
 	return rows;
 }
 
+
+	template<typename FPP>
+bool MatDense<FPP,Cpu>::eq_cols(const MatDense<FPP, Cpu> & other, faust_unsigned_int id_this, faust_unsigned_int id_other, const Real<FPP>& precision) const
+{
+	if(this->getNbRow() != other.getNbRow()) return false;
+	for(int i=0;i<this->getNbRow();i++)
+	{
+		if(std::abs((*this)(i, id_this)-other(i, id_other)) > precision)
+			return false;
+	}
+	return true;
+}
+
+	template<typename FPP>
+bool MatDense<FPP,Cpu>::eq_rows(const MatDense<FPP, Cpu> & other, faust_unsigned_int id_this, faust_unsigned_int id_other, const Real<FPP>& precision) const
+{
+	if(this->getNbCol() != other.getNbCol()) return false;
+	for(int j=0;j<this->getNbCol();j++)
+	{
+		if(std::abs((*this)(id_this,j)-other(id_other,j)) > precision)
+			return false;
+	}
+	return true;
+}
+
+template<typename FPP>
+void MatDense<FPP, Cpu>::best_low_rank(const int &r, MatDense<FPP,Cpu> &bestX, MatDense<FPP, Cpu> &bestY) const
+{
+	Eigen::JacobiSVD<Eigen::Matrix<FPP, Eigen::Dynamic, Eigen::Dynamic>> svd(this->mat, Eigen::ComputeThinU | Eigen::ComputeThinV);
+	bestX.mat = svd.matrixU().block(0, 0, this->getNbRow(), r) * svd.singularValues().block(0, 0, r, r).asDiagonal();
+	bestY.mat = svd.matrixV().block(0, 0, this->getNbCol(), r) * svd.singularValues().block(0, 0, r, r).asDiagonal();
+}
+
+	template<typename FPP>
+std::vector<int> MatDense<FPP, Cpu>::col_nonzero_inds(faust_unsigned_int col_id) const
+{
+	std::vector<int> ids;
+	auto data_ptr = this->getData()+col_id*this->getNbRow();
+	for(int i=0;i<this->getNbRow();i++)
+	{
+		if(data_ptr[i]) ids.push_back(i);
+	}
+	return ids;
+}
+
+template<typename FPP>
+std::vector<int> MatDense<FPP, Cpu>::row_nonzero_inds(faust_unsigned_int row_id) const
+{
+	std::vector<int> ids;
+	auto data_ptr = this->getData();
+	for(int j=0;j<this->getNbRow();j++)
+		if(data_ptr[j*this->getNbRow()+row_id]) ids.push_back(j);
+	return ids;
+}
+
+template<typename FPP>
+void MatDense<FPP, Cpu>::submatrix(const std::vector<int> &row_ids, const std::vector<int> &col_ids, MatDense<FPP, Cpu> & submat) const
+{
+	if(this->dim1 != row_ids.size() || this->dim2 != col_ids.size())
+		submat.resize(row_ids.size(), col_ids.size());
+	submat.mat = mat(row_ids, col_ids);
+	std::cout << submat.mat << std::endl;
+}
+
+template<typename FPP>
+FPP MatDense<FPP,Cpu>::sum_col(faust_unsigned_int id) const
+{
+	FPP sum = (FPP)0;
+	for(int i=0;i<this->getNbRow();i++)
+		sum += (*this)(i, id);
+	return sum;
+}
+
+	template<typename FPP>
+FPP MatDense<FPP,Cpu>::sum_row(faust_unsigned_int id) const
+{
+	FPP sum = (FPP)0;
+	for(int i=0;i<this->getNbCol();i++)
+		sum += (*this)(id, i);
+	return sum;
+}
+
 	template<typename FPP>
 MatDense<FPP,Cpu> MatDense<FPP,Cpu>::get_block(faust_unsigned_int i, faust_unsigned_int j, faust_unsigned_int nrows, faust_unsigned_int ncols)
 {