assertEquals( 5.5, col_means_matrix.get(0, 2), 0.0);
Matrix col_mean_matrix_2 = MatrixUtils.mean(m, 0);
assertEquals(1, col_mean_matrix_2.numRows() );
assertEquals(m.numCols(), col_mean_matrix_2.numCols() );
assertEquals( 2.5, col_mean_matrix_2.get(0, 0), 0.0);
assertEquals( 3.5, col_mean_matrix_2.get(0, 1), 0.0);
assertEquals( 5.5, col_mean_matrix_2.get(0, 2), 0.0);