public void testCloning() {
        MatrixSeries s1 = new MatrixSeries("Series", 2, 3);
        s1.update(0, 0, 1.1);
        MatrixSeriesCollection c1 = new MatrixSeriesCollection();
        c1.addSeries(s1);
        MatrixSeriesCollection c2 = null;
        try {
            c2 = (MatrixSeriesCollection) c1.clone();
        }
        catch (CloneNotSupportedException e) {
            e.printStackTrace();
        }
        assertTrue(c1 != c2);
        assertTrue(c1.getClass() == c2.getClass());
        assertTrue(c1.equals(c2));

        // check independence
        s1.setDescription("XYZ");
        assertFalse(c1.equals(c2));