diff --git a/MathLib/LinAlg/Dense/DenseMatrix-impl.h b/MathLib/LinAlg/Dense/DenseMatrix-impl.h
index 1bd2e873c1b61c3587a4d30674343c5669cfbea4..0d871635b057c9adee7f85dc4c63b5127e02d12b 100644
--- a/MathLib/LinAlg/Dense/DenseMatrix-impl.h
+++ b/MathLib/LinAlg/Dense/DenseMatrix-impl.h
@@ -276,6 +276,7 @@ template <typename FP_TYPE, typename IDX_TYPE>
 void
 DenseMatrix<FP_TYPE, IDX_TYPE>::write (std::ostream &out) const
 {
+	out << _n_rows << " " << _n_cols << "\n";
 	for (IDX_TYPE i = 0; i < _n_rows; i++) {
 		for (IDX_TYPE j = 0; j < _n_cols; j++) {
 			out << _data[address(i, j)] << "\t";