def test_groupby_agg_err_catching(err_cls):
# make sure we suppress anything other than TypeError or AssertionError
# in _python_agg_general
# Use a non-standard EA to make sure we don't go down ndarray paths
from pandas.tests.extension.decimal.array import DecimalArray, make_data, to_decimal
data = make_data()[:5]
df = pd.DataFrame({
"id1": [0, 0, 0, 1, 1],
"id2": [0, 1, 0, 1, 1],
"decimals": DecimalArray(data)
})
expected = pd.Series(to_decimal([data[0], data[3]]))
def weird_func(x):
# weird function that raise something other than TypeError or IndexError
# in _python_agg_general
if len(x) == 0:
raise err_cls
return x.iloc[0]
result = df["decimals"].groupby(df["id1"]).agg(weird_func)
tm.assert_series_equal(result, expected, check_names=False)
def test_groupby_agg():
# Ensure that the result of agg is inferred to be decimal dtype
# https://github.com/pandas-dev/pandas/issues/29141
data = make_data()[:5]
df = pd.DataFrame(
{"id1": [0, 0, 0, 1, 1], "id2": [0, 1, 0, 1, 1], "decimals": DecimalArray(data)}
)
# single key, selected column
expected = pd.Series(to_decimal([data[0], data[3]]))
result = df.groupby("id1")["decimals"].agg(lambda x: x.iloc[0])
tm.assert_series_equal(result, expected, check_names=False)
result = df["decimals"].groupby(df["id1"]).agg(lambda x: x.iloc[0])
tm.assert_series_equal(result, expected, check_names=False)
# multiple keys, selected column
expected = pd.Series(
to_decimal([data[0], data[1], data[3]]),
index=pd.MultiIndex.from_tuples([(0, 0), (0, 1), (1, 1)]),
)
result = df.groupby(["id1", "id2"])["decimals"].agg(lambda x: x.iloc[0])
tm.assert_series_equal(result, expected, check_names=False)
result = df["decimals"].groupby([df["id1"], df["id2"]]).agg(lambda x: x.iloc[0])
tm.assert_series_equal(result, expected, check_names=False)
# multiple columns
expected = pd.DataFrame({"id2": [0, 1], "decimals": to_decimal([data[0], data[3]])})
result = df.groupby("id1").agg(lambda x: x.iloc[0])
tm.assert_frame_equal(result, expected, check_names=False)
def test_groupby_agg_ea_method(monkeypatch):
# Ensure that the result of agg is inferred to be decimal dtype
# https://github.com/pandas-dev/pandas/issues/29141
def DecimalArray__my_sum(self):
return np.sum(np.array(self))
monkeypatch.setattr(DecimalArray, "my_sum", DecimalArray__my_sum, raising=False)
data = make_data()[:5]
df = pd.DataFrame({"id": [0, 0, 0, 1, 1], "decimals": DecimalArray(data)})
expected = pd.Series(to_decimal([data[0] + data[1] + data[2], data[3] + data[4]]))
result = df.groupby("id")["decimals"].agg(lambda x: x.values.my_sum())
tm.assert_series_equal(result, expected, check_names=False)
s = pd.Series(DecimalArray(data))
result = s.groupby(np.array([0, 0, 0, 1, 1])).agg(lambda x: x.values.my_sum())
tm.assert_series_equal(result, expected, check_names=False)
def test_indexing_no_materialize(monkeypatch):
# See https://github.com/pandas-dev/pandas/issues/29708
# Ensure that indexing operations do not materialize (convert to a numpy
# array) the ExtensionArray unnecessary
def DecimalArray__array__(self, dtype=None):
raise Exception("tried to convert a DecimalArray to a numpy array")
monkeypatch.setattr(DecimalArray, "__array__", DecimalArray__array__, raising=False)
data = make_data()
s = pd.Series(DecimalArray(data))
df = pd.DataFrame({"a": s, "b": range(len(s))})
# ensure the following operations do not raise an error
s[s > 0.5]
df[s > 0.5]
s.at[0]
df.at[0, "a"]
def data():
return DecimalArray(make_data())
