craftbeerpi4-pione/venv/lib/python3.8/site-packages/pandas/tests/groupby/test_missing.py

128 lines
3.9 KiB
Python

import numpy as np
import pytest
import pandas as pd
from pandas import DataFrame, Index, date_range
import pandas._testing as tm
@pytest.mark.parametrize("func", ["ffill", "bfill"])
def test_groupby_column_index_name_lost_fill_funcs(func):
# GH: 29764 groupby loses index sometimes
df = DataFrame(
[[1, 1.0, -1.0], [1, np.nan, np.nan], [1, 2.0, -2.0]],
columns=Index(["type", "a", "b"], name="idx"),
)
df_grouped = df.groupby(["type"])[["a", "b"]]
result = getattr(df_grouped, func)().columns
expected = Index(["a", "b"], name="idx")
tm.assert_index_equal(result, expected)
@pytest.mark.parametrize("func", ["ffill", "bfill"])
def test_groupby_fill_duplicate_column_names(func):
# GH: 25610 ValueError with duplicate column names
df1 = DataFrame({"field1": [1, 3, 4], "field2": [1, 3, 4]})
df2 = DataFrame({"field1": [1, np.nan, 4]})
df_grouped = pd.concat([df1, df2], axis=1).groupby(by=["field2"])
expected = DataFrame(
[[1, 1.0], [3, np.nan], [4, 4.0]], columns=["field1", "field1"]
)
result = getattr(df_grouped, func)()
tm.assert_frame_equal(result, expected)
def test_ffill_missing_arguments():
# GH 14955
df = DataFrame({"a": [1, 2], "b": [1, 1]})
with pytest.raises(ValueError, match="Must specify a fill"):
df.groupby("b").fillna()
def test_fill_consistency():
# GH9221
# pass thru keyword arguments to the generated wrapper
# are set if the passed kw is None (only)
df = DataFrame(
index=pd.MultiIndex.from_product(
[["value1", "value2"], date_range("2014-01-01", "2014-01-06")]
),
columns=Index(["1", "2"], name="id"),
)
df["1"] = [
np.nan,
1,
np.nan,
np.nan,
11,
np.nan,
np.nan,
2,
np.nan,
np.nan,
22,
np.nan,
]
df["2"] = [
np.nan,
3,
np.nan,
np.nan,
33,
np.nan,
np.nan,
4,
np.nan,
np.nan,
44,
np.nan,
]
expected = df.groupby(level=0, axis=0).fillna(method="ffill")
result = df.T.groupby(level=0, axis=1).fillna(method="ffill").T
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize("method", ["ffill", "bfill"])
@pytest.mark.parametrize("dropna", [True, False])
@pytest.mark.parametrize("has_nan_group", [True, False])
def test_ffill_handles_nan_groups(dropna, method, has_nan_group):
# GH 34725
df_without_nan_rows = DataFrame([(1, 0.1), (2, 0.2)])
ridx = [-1, 0, -1, -1, 1, -1]
df = df_without_nan_rows.reindex(ridx).reset_index(drop=True)
group_b = np.nan if has_nan_group else "b"
df["group_col"] = pd.Series(["a"] * 3 + [group_b] * 3)
grouped = df.groupby(by="group_col", dropna=dropna)
result = getattr(grouped, method)(limit=None)
expected_rows = {
("ffill", True, True): [-1, 0, 0, -1, -1, -1],
("ffill", True, False): [-1, 0, 0, -1, 1, 1],
("ffill", False, True): [-1, 0, 0, -1, 1, 1],
("ffill", False, False): [-1, 0, 0, -1, 1, 1],
("bfill", True, True): [0, 0, -1, -1, -1, -1],
("bfill", True, False): [0, 0, -1, 1, 1, -1],
("bfill", False, True): [0, 0, -1, 1, 1, -1],
("bfill", False, False): [0, 0, -1, 1, 1, -1],
}
ridx = expected_rows.get((method, dropna, has_nan_group))
expected = df_without_nan_rows.reindex(ridx).reset_index(drop=True)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize("min_count, value", [(2, np.nan), (-1, 1.0)])
@pytest.mark.parametrize("func", ["first", "last", "max", "min"])
def test_min_count(func, min_count, value):
# GH#37821
df = DataFrame({"a": [1] * 3, "b": [1, np.nan, np.nan], "c": [np.nan] * 3})
result = getattr(df.groupby("a"), func)(min_count=min_count)
expected = DataFrame({"b": [value], "c": [np.nan]}, index=Index([1], name="a"))
tm.assert_frame_equal(result, expected)