Included a description of the method

Matrix/pzfmatrix.h

@@ -217,6 +217,16 @@ class TPZFMatrix: public TPZMatrix<TVar> {
     static void MultAdd(const TVar *ptr, int64_t rows, int64_t cols, const TPZFMatrix<TVar> &x,const TPZFMatrix<TVar> &y, TPZFMatrix<TVar> &z,
                         const TVar alpha=1.,const TVar beta = 0.,const int opt = 0);
 
+    /**
+     * @brief It computes this += alpha*(A * B), where A or B can be transposed.
+     * @param i Is the row of (this) where the first element of the matrices product should be added 
+     * @param j Is the column of (this) where the first element of the matrices product should be added 
+     * @param A Is A on the above operation
+     * @param transpA Indicates if A is Transpose or not
+     * @param B Is B on the above operation
+     * @param transpB Indicates if B is Transpose or not
+     * @param alpha Is alpha on the above operation
+     */
     virtual void AddContribution(int64_t i, int64_t j, const TPZFMatrix<TVar> & A, bool transpA, const TPZFMatrix<TVar>& B, 
 						 		 bool transpB, const TVar alpha = 1.0) override;
 

UnitTest_PZ/TestMatrix/TestMatrix.cpp

@@ -1815,7 +1815,7 @@ void TestingAddContribution(int nrows, int ncols, int ntype)
       }
       case 1: // Multiplying matrices with incompatible dimensions
       {
-          REQUIRE_THROWS(C1.AddContribution(0, 0, A, false, B, false, 1.0)); // this will fail because we are multiplying A*B that have the same dimensions
+          REQUIRE_THROWS(C1.AddContribution(0, 0, A, false, B, false, 1.0)); // this will fail for not square matrices, as A and B have the same sizes
           break;
       }
       case 2: // Adding a contribution out of matrix bounds