Add missing assertion

src/algebra/CRSMatrixDescriptor.hpp

@@ -35,7 +35,7 @@ class CRSMatrixDescriptor
     Array<IndexType> row_map(m_nb_rows + 1);
     row_map[0] = 0;
     for (IndexType i = 0; i < m_nb_rows; ++i) {
-      Assert(non_zeros[i] >= 0);
+      Assert((non_zeros[i] >= 0) and (non_zeros[i] <= m_nb_columns));
       row_map[i + 1] = row_map[i] + non_zeros[i];
     }