* Some checks for the clear() method.
*/
public void testClear() {
VectorSeries s1 = new VectorSeries("S1");
s1.addChangeListener(this);
s1.clear();
assertNull(this.lastEvent);
assertTrue(s1.isEmpty());
s1.add(1.0, 2.0, 3.0, 4.0);
assertFalse(s1.isEmpty());
s1.clear();