@Test
public void testEntropy() throws Exception {

  assertEquals(1.386294, LogLikelihood.entropy(1, 1), 0.0001);
  assertEquals(0.0, LogLikelihood.entropy(1), 0.0);
  //TODO: more tests here
  try {
    LogLikelihood.entropy(-1, -1); //exception
    fail();
  } catch (IllegalArgumentException e) {
  }
}