Inzynierka/Lib/site-packages/pandas/tests/io/pytables/test_categorical.py
2023-06-02 12:51:02 +02:00

217 lines
6.8 KiB
Python

import numpy as np
import pytest
from pandas import (
Categorical,
DataFrame,
Series,
_testing as tm,
concat,
read_hdf,
)
from pandas.tests.io.pytables.common import (
_maybe_remove,
ensure_clean_store,
)
pytestmark = [
pytest.mark.single_cpu,
]
def test_categorical(setup_path):
with ensure_clean_store(setup_path) as store:
# Basic
_maybe_remove(store, "s")
s = Series(
Categorical(
["a", "b", "b", "a", "a", "c"],
categories=["a", "b", "c", "d"],
ordered=False,
)
)
store.append("s", s, format="table")
result = store.select("s")
tm.assert_series_equal(s, result)
_maybe_remove(store, "s_ordered")
s = Series(
Categorical(
["a", "b", "b", "a", "a", "c"],
categories=["a", "b", "c", "d"],
ordered=True,
)
)
store.append("s_ordered", s, format="table")
result = store.select("s_ordered")
tm.assert_series_equal(s, result)
_maybe_remove(store, "df")
df = DataFrame({"s": s, "vals": [1, 2, 3, 4, 5, 6]})
store.append("df", df, format="table")
result = store.select("df")
tm.assert_frame_equal(result, df)
# Dtypes
_maybe_remove(store, "si")
s = Series([1, 1, 2, 2, 3, 4, 5]).astype("category")
store.append("si", s)
result = store.select("si")
tm.assert_series_equal(result, s)
_maybe_remove(store, "si2")
s = Series([1, 1, np.nan, 2, 3, 4, 5]).astype("category")
store.append("si2", s)
result = store.select("si2")
tm.assert_series_equal(result, s)
# Multiple
_maybe_remove(store, "df2")
df2 = df.copy()
df2["s2"] = Series(list("abcdefg")).astype("category")
store.append("df2", df2)
result = store.select("df2")
tm.assert_frame_equal(result, df2)
# Make sure the metadata is OK
info = store.info()
assert "/df2 " in info
# df2._mgr.blocks[0] and df2._mgr.blocks[2] are Categorical
assert "/df2/meta/values_block_0/meta" in info
assert "/df2/meta/values_block_2/meta" in info
# unordered
_maybe_remove(store, "s2")
s = Series(
Categorical(
["a", "b", "b", "a", "a", "c"],
categories=["a", "b", "c", "d"],
ordered=False,
)
)
store.append("s2", s, format="table")
result = store.select("s2")
tm.assert_series_equal(result, s)
# Query
_maybe_remove(store, "df3")
store.append("df3", df, data_columns=["s"])
expected = df[df.s.isin(["b", "c"])]
result = store.select("df3", where=['s in ["b","c"]'])
tm.assert_frame_equal(result, expected)
expected = df[df.s.isin(["b", "c"])]
result = store.select("df3", where=['s = ["b","c"]'])
tm.assert_frame_equal(result, expected)
expected = df[df.s.isin(["d"])]
result = store.select("df3", where=['s in ["d"]'])
tm.assert_frame_equal(result, expected)
expected = df[df.s.isin(["f"])]
result = store.select("df3", where=['s in ["f"]'])
tm.assert_frame_equal(result, expected)
# Appending with same categories is ok
store.append("df3", df)
df = concat([df, df])
expected = df[df.s.isin(["b", "c"])]
result = store.select("df3", where=['s in ["b","c"]'])
tm.assert_frame_equal(result, expected)
# Appending must have the same categories
df3 = df.copy()
df3["s"] = df3["s"].cat.remove_unused_categories()
msg = "cannot append a categorical with different categories to the existing"
with pytest.raises(ValueError, match=msg):
store.append("df3", df3)
# Remove, and make sure meta data is removed (its a recursive
# removal so should be).
result = store.select("df3/meta/s/meta")
assert result is not None
store.remove("df3")
with pytest.raises(
KeyError, match="'No object named df3/meta/s/meta in the file'"
):
store.select("df3/meta/s/meta")
def test_categorical_conversion(tmp_path, setup_path):
# GH13322
# Check that read_hdf with categorical columns doesn't return rows if
# where criteria isn't met.
obsids = ["ESP_012345_6789", "ESP_987654_3210"]
imgids = ["APF00006np", "APF0001imm"]
data = [4.3, 9.8]
# Test without categories
df = DataFrame({"obsids": obsids, "imgids": imgids, "data": data})
# We are expecting an empty DataFrame matching types of df
expected = df.iloc[[], :]
path = tmp_path / setup_path
df.to_hdf(path, "df", format="table", data_columns=True)
result = read_hdf(path, "df", where="obsids=B")
tm.assert_frame_equal(result, expected)
# Test with categories
df.obsids = df.obsids.astype("category")
df.imgids = df.imgids.astype("category")
# We are expecting an empty DataFrame matching types of df
expected = df.iloc[[], :]
path = tmp_path / setup_path
df.to_hdf(path, "df", format="table", data_columns=True)
result = read_hdf(path, "df", where="obsids=B")
tm.assert_frame_equal(result, expected)
def test_categorical_nan_only_columns(tmp_path, setup_path):
# GH18413
# Check that read_hdf with categorical columns with NaN-only values can
# be read back.
df = DataFrame(
{
"a": ["a", "b", "c", np.nan],
"b": [np.nan, np.nan, np.nan, np.nan],
"c": [1, 2, 3, 4],
"d": Series([None] * 4, dtype=object),
}
)
df["a"] = df.a.astype("category")
df["b"] = df.b.astype("category")
df["d"] = df.b.astype("category")
expected = df
path = tmp_path / setup_path
df.to_hdf(path, "df", format="table", data_columns=True)
result = read_hdf(path, "df")
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"where, df, expected",
[
('col=="q"', DataFrame({"col": ["a", "b", "s"]}), DataFrame({"col": []})),
('col=="a"', DataFrame({"col": ["a", "b", "s"]}), DataFrame({"col": ["a"]})),
],
)
def test_convert_value(
tmp_path, setup_path, where: str, df: DataFrame, expected: DataFrame
):
# GH39420
# Check that read_hdf with categorical columns can filter by where condition.
df.col = df.col.astype("category")
max_widths = {"col": 1}
categorical_values = sorted(df.col.unique())
expected.col = expected.col.astype("category")
expected.col = expected.col.cat.set_categories(categorical_values)
path = tmp_path / setup_path
df.to_hdf(path, "df", format="table", min_itemsize=max_widths)
result = read_hdf(path, where=where)
tm.assert_frame_equal(result, expected)