projektAI/venv/Lib/site-packages/pandas/tests/frame/methods/test_join.py
2021-06-06 22:13:05 +02:00

365 lines
11 KiB
Python

from datetime import datetime
import numpy as np
import pytest
import pandas as pd
from pandas import DataFrame, Index, MultiIndex, date_range, period_range
import pandas._testing as tm
@pytest.fixture
def frame_with_period_index():
return DataFrame(
data=np.arange(20).reshape(4, 5),
columns=list("abcde"),
index=period_range(start="2000", freq="A", periods=4),
)
@pytest.fixture
def left():
return DataFrame({"a": [20, 10, 0]}, index=[2, 1, 0])
@pytest.fixture
def right():
return DataFrame({"b": [300, 100, 200]}, index=[3, 1, 2])
@pytest.mark.parametrize(
"how, sort, expected",
[
("inner", False, DataFrame({"a": [20, 10], "b": [200, 100]}, index=[2, 1])),
("inner", True, DataFrame({"a": [10, 20], "b": [100, 200]}, index=[1, 2])),
(
"left",
False,
DataFrame({"a": [20, 10, 0], "b": [200, 100, np.nan]}, index=[2, 1, 0]),
),
(
"left",
True,
DataFrame({"a": [0, 10, 20], "b": [np.nan, 100, 200]}, index=[0, 1, 2]),
),
(
"right",
False,
DataFrame({"a": [np.nan, 10, 20], "b": [300, 100, 200]}, index=[3, 1, 2]),
),
(
"right",
True,
DataFrame({"a": [10, 20, np.nan], "b": [100, 200, 300]}, index=[1, 2, 3]),
),
(
"outer",
False,
DataFrame(
{"a": [0, 10, 20, np.nan], "b": [np.nan, 100, 200, 300]},
index=[0, 1, 2, 3],
),
),
(
"outer",
True,
DataFrame(
{"a": [0, 10, 20, np.nan], "b": [np.nan, 100, 200, 300]},
index=[0, 1, 2, 3],
),
),
],
)
def test_join(left, right, how, sort, expected):
result = left.join(right, how=how, sort=sort)
tm.assert_frame_equal(result, expected)
def test_join_index(float_frame):
# left / right
f = float_frame.loc[float_frame.index[:10], ["A", "B"]]
f2 = float_frame.loc[float_frame.index[5:], ["C", "D"]].iloc[::-1]
joined = f.join(f2)
tm.assert_index_equal(f.index, joined.index)
expected_columns = Index(["A", "B", "C", "D"])
tm.assert_index_equal(joined.columns, expected_columns)
joined = f.join(f2, how="left")
tm.assert_index_equal(joined.index, f.index)
tm.assert_index_equal(joined.columns, expected_columns)
joined = f.join(f2, how="right")
tm.assert_index_equal(joined.index, f2.index)
tm.assert_index_equal(joined.columns, expected_columns)
# inner
joined = f.join(f2, how="inner")
tm.assert_index_equal(joined.index, f.index[5:10])
tm.assert_index_equal(joined.columns, expected_columns)
# outer
joined = f.join(f2, how="outer")
tm.assert_index_equal(joined.index, float_frame.index.sort_values())
tm.assert_index_equal(joined.columns, expected_columns)
with pytest.raises(ValueError, match="join method"):
f.join(f2, how="foo")
# corner case - overlapping columns
msg = "columns overlap but no suffix"
for how in ("outer", "left", "inner"):
with pytest.raises(ValueError, match=msg):
float_frame.join(float_frame, how=how)
def test_join_index_more(float_frame):
af = float_frame.loc[:, ["A", "B"]]
bf = float_frame.loc[::2, ["C", "D"]]
expected = af.copy()
expected["C"] = float_frame["C"][::2]
expected["D"] = float_frame["D"][::2]
result = af.join(bf)
tm.assert_frame_equal(result, expected)
result = af.join(bf, how="right")
tm.assert_frame_equal(result, expected[::2])
result = bf.join(af, how="right")
tm.assert_frame_equal(result, expected.loc[:, result.columns])
def test_join_index_series(float_frame):
df = float_frame.copy()
s = df.pop(float_frame.columns[-1])
joined = df.join(s)
# TODO should this check_names ?
tm.assert_frame_equal(joined, float_frame, check_names=False)
s.name = None
with pytest.raises(ValueError, match="must have a name"):
df.join(s)
def test_join_overlap(float_frame):
df1 = float_frame.loc[:, ["A", "B", "C"]]
df2 = float_frame.loc[:, ["B", "C", "D"]]
joined = df1.join(df2, lsuffix="_df1", rsuffix="_df2")
df1_suf = df1.loc[:, ["B", "C"]].add_suffix("_df1")
df2_suf = df2.loc[:, ["B", "C"]].add_suffix("_df2")
no_overlap = float_frame.loc[:, ["A", "D"]]
expected = df1_suf.join(df2_suf).join(no_overlap)
# column order not necessarily sorted
tm.assert_frame_equal(joined, expected.loc[:, joined.columns])
def test_join_period_index(frame_with_period_index):
other = frame_with_period_index.rename(columns=lambda key: f"{key}{key}")
joined_values = np.concatenate([frame_with_period_index.values] * 2, axis=1)
joined_cols = frame_with_period_index.columns.append(other.columns)
joined = frame_with_period_index.join(other)
expected = DataFrame(
data=joined_values, columns=joined_cols, index=frame_with_period_index.index
)
tm.assert_frame_equal(joined, expected)
def test_join_left_sequence_non_unique_index():
# https://github.com/pandas-dev/pandas/issues/19607
df1 = DataFrame({"a": [0, 10, 20]}, index=[1, 2, 3])
df2 = DataFrame({"b": [100, 200, 300]}, index=[4, 3, 2])
df3 = DataFrame({"c": [400, 500, 600]}, index=[2, 2, 4])
joined = df1.join([df2, df3], how="left")
expected = DataFrame(
{
"a": [0, 10, 10, 20],
"b": [np.nan, 300, 300, 200],
"c": [np.nan, 400, 500, np.nan],
},
index=[1, 2, 2, 3],
)
tm.assert_frame_equal(joined, expected)
@pytest.mark.parametrize("sort_kw", [True, False])
def test_suppress_future_warning_with_sort_kw(sort_kw):
a = DataFrame({"col1": [1, 2]}, index=["c", "a"])
b = DataFrame({"col2": [4, 5]}, index=["b", "a"])
c = DataFrame({"col3": [7, 8]}, index=["a", "b"])
expected = DataFrame(
{
"col1": {"a": 2.0, "b": float("nan"), "c": 1.0},
"col2": {"a": 5.0, "b": 4.0, "c": float("nan")},
"col3": {"a": 7.0, "b": 8.0, "c": float("nan")},
}
)
if sort_kw is False:
expected = expected.reindex(index=["c", "a", "b"])
with tm.assert_produces_warning(None, check_stacklevel=False):
result = a.join([b, c], how="outer", sort=sort_kw)
tm.assert_frame_equal(result, expected)
class TestDataFrameJoin:
def test_join(self, multiindex_dataframe_random_data):
frame = multiindex_dataframe_random_data
a = frame.loc[frame.index[:5], ["A"]]
b = frame.loc[frame.index[2:], ["B", "C"]]
joined = a.join(b, how="outer").reindex(frame.index)
expected = frame.copy()
expected.values[np.isnan(joined.values)] = np.nan
assert not np.isnan(joined.values).all()
# TODO what should join do with names ?
tm.assert_frame_equal(joined, expected, check_names=False)
def test_join_segfault(self):
# GH#1532
df1 = DataFrame({"a": [1, 1], "b": [1, 2], "x": [1, 2]})
df2 = DataFrame({"a": [2, 2], "b": [1, 2], "y": [1, 2]})
df1 = df1.set_index(["a", "b"])
df2 = df2.set_index(["a", "b"])
# it works!
for how in ["left", "right", "outer"]:
df1.join(df2, how=how)
def test_join_str_datetime(self):
str_dates = ["20120209", "20120222"]
dt_dates = [datetime(2012, 2, 9), datetime(2012, 2, 22)]
A = DataFrame(str_dates, index=range(2), columns=["aa"])
C = DataFrame([[1, 2], [3, 4]], index=str_dates, columns=dt_dates)
tst = A.join(C, on="aa")
assert len(tst.columns) == 3
def test_join_multiindex_leftright(self):
# GH 10741
df1 = DataFrame(
[
["a", "x", 0.471780],
["a", "y", 0.774908],
["a", "z", 0.563634],
["b", "x", -0.353756],
["b", "y", 0.368062],
["b", "z", -1.721840],
["c", "x", 1],
["c", "y", 2],
["c", "z", 3],
],
columns=["first", "second", "value1"],
).set_index(["first", "second"])
df2 = DataFrame([["a", 10], ["b", 20]], columns=["first", "value2"]).set_index(
["first"]
)
exp = DataFrame(
[
[0.471780, 10],
[0.774908, 10],
[0.563634, 10],
[-0.353756, 20],
[0.368062, 20],
[-1.721840, 20],
[1.000000, np.nan],
[2.000000, np.nan],
[3.000000, np.nan],
],
index=df1.index,
columns=["value1", "value2"],
)
# these must be the same results (but columns are flipped)
tm.assert_frame_equal(df1.join(df2, how="left"), exp)
tm.assert_frame_equal(df2.join(df1, how="right"), exp[["value2", "value1"]])
exp_idx = pd.MultiIndex.from_product(
[["a", "b"], ["x", "y", "z"]], names=["first", "second"]
)
exp = DataFrame(
[
[0.471780, 10],
[0.774908, 10],
[0.563634, 10],
[-0.353756, 20],
[0.368062, 20],
[-1.721840, 20],
],
index=exp_idx,
columns=["value1", "value2"],
)
tm.assert_frame_equal(df1.join(df2, how="right"), exp)
tm.assert_frame_equal(df2.join(df1, how="left"), exp[["value2", "value1"]])
def test_merge_join_different_levels(self):
# GH#9455
# first dataframe
df1 = DataFrame(columns=["a", "b"], data=[[1, 11], [0, 22]])
# second dataframe
columns = MultiIndex.from_tuples([("a", ""), ("c", "c1")])
df2 = DataFrame(columns=columns, data=[[1, 33], [0, 44]])
# merge
columns = ["a", "b", ("c", "c1")]
expected = DataFrame(columns=columns, data=[[1, 11, 33], [0, 22, 44]])
with tm.assert_produces_warning(UserWarning):
result = pd.merge(df1, df2, on="a")
tm.assert_frame_equal(result, expected)
# join, see discussion in GH#12219
columns = ["a", "b", ("a", ""), ("c", "c1")]
expected = DataFrame(columns=columns, data=[[1, 11, 0, 44], [0, 22, 1, 33]])
with tm.assert_produces_warning(UserWarning):
result = df1.join(df2, on="a")
tm.assert_frame_equal(result, expected)
def test_frame_join_tzaware(self):
test1 = DataFrame(
np.zeros((6, 3)),
index=date_range(
"2012-11-15 00:00:00", periods=6, freq="100L", tz="US/Central"
),
)
test2 = DataFrame(
np.zeros((3, 3)),
index=date_range(
"2012-11-15 00:00:00", periods=3, freq="250L", tz="US/Central"
),
columns=range(3, 6),
)
result = test1.join(test2, how="outer")
expected = test1.index.union(test2.index)
tm.assert_index_equal(result.index, expected)
assert result.index.tz.zone == "US/Central"