def test_tick_sets_initialized_rate(self):
ewma = EWMA(0.5)
ewma.update(3)
ewma.tick()
ewma.update(2)
ewma.tick()
self.assertEqual(ewma.rate, 0.5)
def test_tick_sets_uninitialized_rate(self):
ewma = EWMA.one_minute()
ewma.update(3)
ewma.tick()
self.assertEqual(ewma.rate, 3 / 5.0)
def test_update_adds_N(self):
ewma = EWMA.one_minute()
ewma.update(42)
self.assertEqual(ewma._uncounted, 42)
def test_fifteen_minutes_sets_alpha(self):
fifteen_minutes = EWMA.fifteen_minutes()
self.assertAlmostEqual(fifteen_minutes._alpha, 0.00554, 5)
def test_five_minutes_sets_alpha(self):
five_minutes = EWMA.five_minutes()
self.assertAlmostEqual(five_minutes._alpha, 0.01653, 5)
def test_one_minute_sets_alpha(self):
one_minute = EWMA.one_minute()
self.assertAlmostEqual(one_minute._alpha, 0.07996, 5)
