Inzynierka/Lib/site-packages/pandas/tests/groupby/test_groupby_subclass.py
2023-06-02 12:51:02 +02:00

106 lines
3.3 KiB
Python

from datetime import datetime
import numpy as np
import pytest
from pandas import (
DataFrame,
Index,
Series,
)
import pandas._testing as tm
from pandas.tests.groupby import get_groupby_method_args
@pytest.mark.parametrize(
"obj",
[
tm.SubclassedDataFrame({"A": np.arange(0, 10)}),
tm.SubclassedSeries(np.arange(0, 10), name="A"),
],
)
def test_groupby_preserves_subclass(obj, groupby_func):
# GH28330 -- preserve subclass through groupby operations
if isinstance(obj, Series) and groupby_func in {"corrwith"}:
pytest.skip(f"Not applicable for Series and {groupby_func}")
grouped = obj.groupby(np.arange(0, 10))
# Groups should preserve subclass type
assert isinstance(grouped.get_group(0), type(obj))
args = get_groupby_method_args(groupby_func, obj)
result1 = getattr(grouped, groupby_func)(*args)
result2 = grouped.agg(groupby_func, *args)
# Reduction or transformation kernels should preserve type
slices = {"ngroup", "cumcount", "size"}
if isinstance(obj, DataFrame) and groupby_func in slices:
assert isinstance(result1, tm.SubclassedSeries)
else:
assert isinstance(result1, type(obj))
# Confirm .agg() groupby operations return same results
if isinstance(result1, DataFrame):
tm.assert_frame_equal(result1, result2)
else:
tm.assert_series_equal(result1, result2)
def test_groupby_preserves_metadata():
# GH-37343
custom_df = tm.SubclassedDataFrame({"a": [1, 2, 3], "b": [1, 1, 2], "c": [7, 8, 9]})
assert "testattr" in custom_df._metadata
custom_df.testattr = "hello"
for _, group_df in custom_df.groupby("c"):
assert group_df.testattr == "hello"
# GH-45314
def func(group):
assert isinstance(group, tm.SubclassedDataFrame)
assert hasattr(group, "testattr")
return group.testattr
result = custom_df.groupby("c").apply(func)
expected = tm.SubclassedSeries(["hello"] * 3, index=Index([7, 8, 9], name="c"))
tm.assert_series_equal(result, expected)
def func2(group):
assert isinstance(group, tm.SubclassedSeries)
assert hasattr(group, "testattr")
return group.testattr
custom_series = tm.SubclassedSeries([1, 2, 3])
custom_series.testattr = "hello"
result = custom_series.groupby(custom_df["c"]).apply(func2)
tm.assert_series_equal(result, expected)
result = custom_series.groupby(custom_df["c"]).agg(func2)
tm.assert_series_equal(result, expected)
@pytest.mark.parametrize("obj", [DataFrame, tm.SubclassedDataFrame])
def test_groupby_resample_preserves_subclass(obj):
# GH28330 -- preserve subclass through groupby.resample()
df = obj(
{
"Buyer": "Carl Carl Carl Carl Joe Carl".split(),
"Quantity": [18, 3, 5, 1, 9, 3],
"Date": [
datetime(2013, 9, 1, 13, 0),
datetime(2013, 9, 1, 13, 5),
datetime(2013, 10, 1, 20, 0),
datetime(2013, 10, 3, 10, 0),
datetime(2013, 12, 2, 12, 0),
datetime(2013, 9, 2, 14, 0),
],
}
)
df = df.set_index("Date")
# Confirm groupby.resample() preserves dataframe type
result = df.groupby("Buyer").resample("5D").sum()
assert isinstance(result, obj)