def testpopulationstandarddeviation_returns_std(self):
list = [1, 2, 3, 4, 5]
stat = Statistics(list)
actual = stat.standardDeviation()
expected = 1.4142135623730951
self.assertEqual(expected, actual)
def testsamplestandarddeviation_returns_std(self):
list = [1, 2, 3, 4, 5]
stat = Statistics(list)
actual = stat.standardDeviation(population=False)
expected = 1.5811388300841898
self.assertEqual(actual, expected)
def teststandarddeviation_returns_none(self):
emptylist = []
stat = Statistics(emptylist)
actual = stat.standardDeviation()
expected = None
self.assertEqual(expected, actual)
