Inzynierka/Lib/site-packages/pandas/tests/extension/base/reshaping.py
2023-06-02 12:51:02 +02:00

368 lines
13 KiB
Python

import itertools
import numpy as np
import pytest
import pandas as pd
from pandas.api.extensions import ExtensionArray
from pandas.core.internals.blocks import EABackedBlock
from pandas.tests.extension.base.base import BaseExtensionTests
class BaseReshapingTests(BaseExtensionTests):
"""Tests for reshaping and concatenation."""
@pytest.mark.parametrize("in_frame", [True, False])
def test_concat(self, data, in_frame):
wrapped = pd.Series(data)
if in_frame:
wrapped = pd.DataFrame(wrapped)
result = pd.concat([wrapped, wrapped], ignore_index=True)
assert len(result) == len(data) * 2
if in_frame:
dtype = result.dtypes[0]
else:
dtype = result.dtype
assert dtype == data.dtype
if hasattr(result._mgr, "blocks"):
assert isinstance(result._mgr.blocks[0], EABackedBlock)
assert isinstance(result._mgr.arrays[0], ExtensionArray)
@pytest.mark.parametrize("in_frame", [True, False])
def test_concat_all_na_block(self, data_missing, in_frame):
valid_block = pd.Series(data_missing.take([1, 1]), index=[0, 1])
na_block = pd.Series(data_missing.take([0, 0]), index=[2, 3])
if in_frame:
valid_block = pd.DataFrame({"a": valid_block})
na_block = pd.DataFrame({"a": na_block})
result = pd.concat([valid_block, na_block])
if in_frame:
expected = pd.DataFrame({"a": data_missing.take([1, 1, 0, 0])})
self.assert_frame_equal(result, expected)
else:
expected = pd.Series(data_missing.take([1, 1, 0, 0]))
self.assert_series_equal(result, expected)
def test_concat_mixed_dtypes(self, data):
# https://github.com/pandas-dev/pandas/issues/20762
df1 = pd.DataFrame({"A": data[:3]})
df2 = pd.DataFrame({"A": [1, 2, 3]})
df3 = pd.DataFrame({"A": ["a", "b", "c"]}).astype("category")
dfs = [df1, df2, df3]
# dataframes
result = pd.concat(dfs)
expected = pd.concat([x.astype(object) for x in dfs])
self.assert_frame_equal(result, expected)
# series
result = pd.concat([x["A"] for x in dfs])
expected = pd.concat([x["A"].astype(object) for x in dfs])
self.assert_series_equal(result, expected)
# simple test for just EA and one other
result = pd.concat([df1, df2.astype(object)])
expected = pd.concat([df1.astype("object"), df2.astype("object")])
self.assert_frame_equal(result, expected)
result = pd.concat([df1["A"], df2["A"].astype(object)])
expected = pd.concat([df1["A"].astype("object"), df2["A"].astype("object")])
self.assert_series_equal(result, expected)
def test_concat_columns(self, data, na_value):
df1 = pd.DataFrame({"A": data[:3]})
df2 = pd.DataFrame({"B": [1, 2, 3]})
expected = pd.DataFrame({"A": data[:3], "B": [1, 2, 3]})
result = pd.concat([df1, df2], axis=1)
self.assert_frame_equal(result, expected)
result = pd.concat([df1["A"], df2["B"]], axis=1)
self.assert_frame_equal(result, expected)
# non-aligned
df2 = pd.DataFrame({"B": [1, 2, 3]}, index=[1, 2, 3])
expected = pd.DataFrame(
{
"A": data._from_sequence(list(data[:3]) + [na_value], dtype=data.dtype),
"B": [np.nan, 1, 2, 3],
}
)
result = pd.concat([df1, df2], axis=1)
self.assert_frame_equal(result, expected)
result = pd.concat([df1["A"], df2["B"]], axis=1)
self.assert_frame_equal(result, expected)
def test_concat_extension_arrays_copy_false(self, data, na_value):
# GH 20756
df1 = pd.DataFrame({"A": data[:3]})
df2 = pd.DataFrame({"B": data[3:7]})
expected = pd.DataFrame(
{
"A": data._from_sequence(list(data[:3]) + [na_value], dtype=data.dtype),
"B": data[3:7],
}
)
result = pd.concat([df1, df2], axis=1, copy=False)
self.assert_frame_equal(result, expected)
def test_concat_with_reindex(self, data):
# GH-33027
a = pd.DataFrame({"a": data[:5]})
b = pd.DataFrame({"b": data[:5]})
result = pd.concat([a, b], ignore_index=True)
expected = pd.DataFrame(
{
"a": data.take(list(range(5)) + ([-1] * 5), allow_fill=True),
"b": data.take(([-1] * 5) + list(range(5)), allow_fill=True),
}
)
self.assert_frame_equal(result, expected)
def test_align(self, data, na_value):
a = data[:3]
b = data[2:5]
r1, r2 = pd.Series(a).align(pd.Series(b, index=[1, 2, 3]))
# Assumes that the ctor can take a list of scalars of the type
e1 = pd.Series(data._from_sequence(list(a) + [na_value], dtype=data.dtype))
e2 = pd.Series(data._from_sequence([na_value] + list(b), dtype=data.dtype))
self.assert_series_equal(r1, e1)
self.assert_series_equal(r2, e2)
def test_align_frame(self, data, na_value):
a = data[:3]
b = data[2:5]
r1, r2 = pd.DataFrame({"A": a}).align(pd.DataFrame({"A": b}, index=[1, 2, 3]))
# Assumes that the ctor can take a list of scalars of the type
e1 = pd.DataFrame(
{"A": data._from_sequence(list(a) + [na_value], dtype=data.dtype)}
)
e2 = pd.DataFrame(
{"A": data._from_sequence([na_value] + list(b), dtype=data.dtype)}
)
self.assert_frame_equal(r1, e1)
self.assert_frame_equal(r2, e2)
def test_align_series_frame(self, data, na_value):
# https://github.com/pandas-dev/pandas/issues/20576
ser = pd.Series(data, name="a")
df = pd.DataFrame({"col": np.arange(len(ser) + 1)})
r1, r2 = ser.align(df)
e1 = pd.Series(
data._from_sequence(list(data) + [na_value], dtype=data.dtype),
name=ser.name,
)
self.assert_series_equal(r1, e1)
self.assert_frame_equal(r2, df)
def test_set_frame_expand_regular_with_extension(self, data):
df = pd.DataFrame({"A": [1] * len(data)})
df["B"] = data
expected = pd.DataFrame({"A": [1] * len(data), "B": data})
self.assert_frame_equal(df, expected)
def test_set_frame_expand_extension_with_regular(self, data):
df = pd.DataFrame({"A": data})
df["B"] = [1] * len(data)
expected = pd.DataFrame({"A": data, "B": [1] * len(data)})
self.assert_frame_equal(df, expected)
def test_set_frame_overwrite_object(self, data):
# https://github.com/pandas-dev/pandas/issues/20555
df = pd.DataFrame({"A": [1] * len(data)}, dtype=object)
df["A"] = data
assert df.dtypes["A"] == data.dtype
def test_merge(self, data, na_value):
# GH-20743
df1 = pd.DataFrame({"ext": data[:3], "int1": [1, 2, 3], "key": [0, 1, 2]})
df2 = pd.DataFrame({"int2": [1, 2, 3, 4], "key": [0, 0, 1, 3]})
res = pd.merge(df1, df2)
exp = pd.DataFrame(
{
"int1": [1, 1, 2],
"int2": [1, 2, 3],
"key": [0, 0, 1],
"ext": data._from_sequence(
[data[0], data[0], data[1]], dtype=data.dtype
),
}
)
self.assert_frame_equal(res, exp[["ext", "int1", "key", "int2"]])
res = pd.merge(df1, df2, how="outer")
exp = pd.DataFrame(
{
"int1": [1, 1, 2, 3, np.nan],
"int2": [1, 2, 3, np.nan, 4],
"key": [0, 0, 1, 2, 3],
"ext": data._from_sequence(
[data[0], data[0], data[1], data[2], na_value], dtype=data.dtype
),
}
)
self.assert_frame_equal(res, exp[["ext", "int1", "key", "int2"]])
def test_merge_on_extension_array(self, data):
# GH 23020
a, b = data[:2]
key = type(data)._from_sequence([a, b], dtype=data.dtype)
df = pd.DataFrame({"key": key, "val": [1, 2]})
result = pd.merge(df, df, on="key")
expected = pd.DataFrame({"key": key, "val_x": [1, 2], "val_y": [1, 2]})
self.assert_frame_equal(result, expected)
# order
result = pd.merge(df.iloc[[1, 0]], df, on="key")
expected = expected.iloc[[1, 0]].reset_index(drop=True)
self.assert_frame_equal(result, expected)
def test_merge_on_extension_array_duplicates(self, data):
# GH 23020
a, b = data[:2]
key = type(data)._from_sequence([a, b, a], dtype=data.dtype)
df1 = pd.DataFrame({"key": key, "val": [1, 2, 3]})
df2 = pd.DataFrame({"key": key, "val": [1, 2, 3]})
result = pd.merge(df1, df2, on="key")
expected = pd.DataFrame(
{
"key": key.take([0, 0, 0, 0, 1]),
"val_x": [1, 1, 3, 3, 2],
"val_y": [1, 3, 1, 3, 2],
}
)
self.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"columns",
[
["A", "B"],
pd.MultiIndex.from_tuples(
[("A", "a"), ("A", "b")], names=["outer", "inner"]
),
],
)
def test_stack(self, data, columns):
df = pd.DataFrame({"A": data[:5], "B": data[:5]})
df.columns = columns
result = df.stack()
expected = df.astype(object).stack()
# we need a second astype(object), in case the constructor inferred
# object -> specialized, as is done for period.
expected = expected.astype(object)
if isinstance(expected, pd.Series):
assert result.dtype == df.iloc[:, 0].dtype
else:
assert all(result.dtypes == df.iloc[:, 0].dtype)
result = result.astype(object)
self.assert_equal(result, expected)
@pytest.mark.parametrize(
"index",
[
# Two levels, uniform.
pd.MultiIndex.from_product(([["A", "B"], ["a", "b"]]), names=["a", "b"]),
# non-uniform
pd.MultiIndex.from_tuples([("A", "a"), ("A", "b"), ("B", "b")]),
# three levels, non-uniform
pd.MultiIndex.from_product([("A", "B"), ("a", "b", "c"), (0, 1, 2)]),
pd.MultiIndex.from_tuples(
[
("A", "a", 1),
("A", "b", 0),
("A", "a", 0),
("B", "a", 0),
("B", "c", 1),
]
),
],
)
@pytest.mark.parametrize("obj", ["series", "frame"])
def test_unstack(self, data, index, obj):
data = data[: len(index)]
if obj == "series":
ser = pd.Series(data, index=index)
else:
ser = pd.DataFrame({"A": data, "B": data}, index=index)
n = index.nlevels
levels = list(range(n))
# [0, 1, 2]
# [(0,), (1,), (2,), (0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
combinations = itertools.chain.from_iterable(
itertools.permutations(levels, i) for i in range(1, n)
)
for level in combinations:
result = ser.unstack(level=level)
assert all(
isinstance(result[col].array, type(data)) for col in result.columns
)
if obj == "series":
# We should get the same result with to_frame+unstack+droplevel
df = ser.to_frame()
alt = df.unstack(level=level).droplevel(0, axis=1)
self.assert_frame_equal(result, alt)
obj_ser = ser.astype(object)
expected = obj_ser.unstack(level=level, fill_value=data.dtype.na_value)
if obj == "series":
assert (expected.dtypes == object).all()
result = result.astype(object)
self.assert_frame_equal(result, expected)
def test_ravel(self, data):
# as long as EA is 1D-only, ravel is a no-op
result = data.ravel()
assert type(result) == type(data)
# Check that we have a view, not a copy
result[0] = result[1]
assert data[0] == data[1]
def test_transpose(self, data):
result = data.transpose()
assert type(result) == type(data)
# check we get a new object
assert result is not data
# If we ever _did_ support 2D, shape should be reversed
assert result.shape == data.shape[::-1]
# Check that we have a view, not a copy
result[0] = result[1]
assert data[0] == data[1]
def test_transpose_frame(self, data):
df = pd.DataFrame({"A": data[:4], "B": data[:4]}, index=["a", "b", "c", "d"])
result = df.T
expected = pd.DataFrame(
{
"a": type(data)._from_sequence([data[0]] * 2, dtype=data.dtype),
"b": type(data)._from_sequence([data[1]] * 2, dtype=data.dtype),
"c": type(data)._from_sequence([data[2]] * 2, dtype=data.dtype),
"d": type(data)._from_sequence([data[3]] * 2, dtype=data.dtype),
},
index=["A", "B"],
)
self.assert_frame_equal(result, expected)
self.assert_frame_equal(np.transpose(np.transpose(df)), df)
self.assert_frame_equal(np.transpose(np.transpose(df[["A"]])), df[["A"]])