Add MatDense::lower_tri()/upper_tri() and a small unit test.

misc/test/CMakeLists.txt

@@ -156,7 +156,7 @@ endif()
 
 
 foreach(TEST_FPP float double)
-	foreach(FILE faust_mult faust_mult_cplx test_Vect_min test_MatDense_min test_MatDense_get_row)
+	foreach(FILE faust_mult faust_mult_cplx test_Vect_min test_MatDense_min test_MatDense_get_row test_MatDense_lower_upper_tri)
 		set(TEST_BIN_FILE ${FILE}_${TEST_FPP})
 		set(TEST_FILE_CPP ${TEST_BIN_FILE}.cpp)
 		message(STATUS ${TEST_FILE_CPP})

misc/test/src/C++/unit/test_MatDense_lower_upper_tri.cpp.in

+
+#define DEBUG_TRI 1
+#include "faust_MatDense.h"
+
+
+#include <complex>
+#include <random>
+
+using namespace Faust;
+typedef @TEST_FPP@ FPP;
+
+
+int main()
+{
+	MatDense<FPP,Cpu>* M = MatDense<FPP,Cpu>::randMat(5,5);
+
+
+	Faust::MatSparse<FPP,Cpu> ltri_M = M->lower_tri();
+
+	ltri_M.Display();
+
+	ltri_M = M->lower_tri(false);
+	ltri_M.Display();
+
+	Faust::MatSparse<FPP,Cpu> utri_M = M->upper_tri();
+	utri_M.Display();
+	utri_M = M->upper_tri(false);
+	utri_M.Display();
+
+	return 0;
+}

src/faust_linear_operator/CPU/faust_MatDense.h

@@ -448,6 +448,19 @@ void spgemm(const Faust::MatSparse<FPP,Cpu> & A,const Faust::MatDense<FPP,Cpu> &
 		static Faust::MatDense<FPP,Cpu>* randMat(faust_unsigned_int num_rows, faust_unsigned_int num_cols, float density);
 		//\param : per_row means the density applies for each line rather than globally for the matrix
 		static Faust::MatDense<FPP,Cpu>* randMat(faust_unsigned_int num_rows, faust_unsigned_int num_cols, float density, bool per_row);
+		/**
+		 * \brief Returns the lower-triangular matrix with or without the diagonal.
+		 *
+		 * param diag true to include the diagonal, false otherwise.
+		 */
+		Faust::MatDense<FPP,Cpu> lower_tri(const bool diag=true) const;
+		/**
+		 * \brief Returns the upper-triangular matrix with or without the diagonal.
+		 *
+		 * param diag true to include the diagonal, false otherwise.
+		 */
+		Faust::MatDense<FPP,Cpu> upper_tri(const bool diag=true) const;
+
 		private:
 		Eigen::Matrix<FPP, Eigen::Dynamic, Eigen::Dynamic> mat;
 		bool isIdentity;

src/faust_linear_operator/CPU/faust_MatDense.hpp

@@ -153,6 +153,44 @@ void Faust::MatDense<FPP,Cpu>::check_dim_validity()
 #endif
 
 }
+
+
+template<typename FPP>
+Faust::MatDense<FPP,Cpu> Faust::MatDense<FPP,Cpu>::lower_tri(const bool diag) const
+{
+	Faust::MatDense<FPP,Cpu> tri = Faust::MatDense<FPP,Cpu>(this->dim1, this->dim2);
+	if(diag)
+		tri.mat = mat.template triangularView<Eigen::Lower>();
+	else
+		tri.mat = mat.template triangularView<Eigen::StrictlyLower>();
+#ifdef DEBUG_TRI
+	cout << "MatDense::lower_tri(" << diag << ")" << endl;
+	cout << "orig. mat.:" << endl;
+	cout << mat << endl;
+	cout << "tri. mat.:" << endl;
+	cout << tri.mat << endl;
+#endif
+	return tri;
+}
+
+template<typename FPP>
+Faust::MatDense<FPP,Cpu> Faust::MatDense<FPP,Cpu>::upper_tri(const bool diag) const
+{
+	Faust::MatDense<FPP,Cpu> tri = Faust::MatDense<FPP,Cpu>(this->dim1, this->dim2);
+	if(diag)
+		tri.mat = mat.template triangularView<Eigen::Upper>();
+	else
+		tri.mat = mat.template triangularView<Eigen::StrictlyUpper>();
+#ifdef DEBUG_TRI
+	cout << "MatDense::upper_tri(" << diag << ")" << endl;
+	cout << "orig. mat.:" << endl;
+	cout << mat << endl;
+	cout << "tri. mat.:" << endl;
+	cout << tri.mat << endl;
+#endif
+	return tri;
+}
+
 	template<typename FPP>
 void Faust::MatDense<FPP,Cpu>::setOnes()
 {