Merge pull request #3069 from KratosMultiphysics/core/add-sum-to-matrix

Adding sum to amatrix interface

kratos/includes/amatrix_interface.h

@@ -607,6 +607,19 @@ template <typename TExpressionType, std::size_t TCategory>
     return AMatrix::SubVector<TExpressionType>(TheExpression.expression(), From,To - From);
 }
 
+
+	template <typename TExpressionType, std::size_t TCategory>
+	typename TExpressionType::data_type sum(
+		AMatrix::MatrixExpression<TExpressionType, TCategory> const& TheExpression) {
+		using data_type = typename TExpressionType::data_type;
+		auto& the_expression = TheExpression.expression();
+		data_type result = data_type();
+		for (std::size_t i = 0; i < the_expression.size(); ++i) {
+			result += the_expression[i];
+		}
+		return result;
+	}
+
 template <typename TExpressionType, std::size_t TCategory>
     typename TExpressionType::data_type norm_frobenius(
     AMatrix::MatrixExpression<TExpressionType, TCategory> const& TheExpression) {
@@ -619,6 +632,7 @@ template <typename TExpressionType, std::size_t TCategory>
     return std::sqrt(result);
 }
 
+
 	template <typename TDataType>
 	class scalar_matrix
 		: public AMatrix::MatrixExpression<scalar_matrix<TDataType>, AMatrix::row_major_access> {

kratos/tests/sources/test_amatrix.cpp

@@ -0,0 +1,37 @@
+//    |  /           |
+//    ' /   __| _` | __|  _ \   __|
+//    . \  |   (   | |   (   |\__ `
+//   _|\_\_|  \__,_|\__|\___/ ____/
+//                   Multi-Physics
+//
+//  License:		 BSD License
+//					 Kratos default license: kratos/license.txt
+//
+//  Main authors:    Pooyan Dadvand
+//
+//
+
+// System includes
+
+
+// External includes
+
+#ifdef KRATOS_USE_AMATRIX   // This macro definition is for the migration period and to be removed afterward please do not use it 
+
+// Project includes
+#include "testing/testing.h"
+#include "includes/amatrix_interface.h"
+
+
+namespace Kratos {
+	namespace Testing {
+
+		KRATOS_TEST_CASE_IN_SUITE(AMatrixSum, KratosCoreFastSuite)
+		{
+			DenseVector<double> a{ 1.0, 2.0, 3.1 };
+			KRATOS_CHECK_EQUAL(sum(a), 6.1);
+		}
+
+    }
+}  // namespace Kratos.
+#endif // ifdef KRATOS_USE_AMATRIX