def test_gini_single():
'''FIXME
test calculating a gini coefficient with a single item in the list
the coefficient should be zero as there's no variation
'''
gini = calculate_gini(pd.Series([1.0]))
assert gini == 0
def test_gini_empty():
'''test calculating a gini coefficient with an empty list
This will cause some warnings from python
'''
gini = calculate_gini(pd.Series([]))
assert math.isnan(gini) is True
def test_gini_four_even():
'''test calculating a gini coefficient with four identical items'''
gini = calculate_gini(pd.Series([1.0, 1.0, 1.0, 1.0]))
assert gini == 0.0
def test_gini_four():
'''test calculating a gini coefficient with four different items'''
gini = calculate_gini(pd.Series([1.0, 2.0, 3.0, 4.0]))
assert gini == 0.25
def test_gini_single():
gini = calculate_gini(pd.Series([1.0]))
assert gini == 0.0
