laywerrobot/lib/python3.6/site-packages/pandas/tests/frame/test_join.py
2020-08-27 21:55:39 +02:00

184 lines
5.6 KiB
Python

# -*- coding: utf-8 -*-
import pytest
import numpy as np
from pandas import DataFrame, Index, PeriodIndex
from pandas.tests.frame.common import TestData
import pandas.util.testing as tm
@pytest.fixture
def frame_with_period_index():
return DataFrame(
data=np.arange(20).reshape(4, 5),
columns=list('abcde'),
index=PeriodIndex(start='2000', freq='A', periods=4))
@pytest.fixture
def frame():
return TestData().frame
@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(frame):
# left / right
f = frame.loc[frame.index[:10], ['A', 'B']]
f2 = frame.loc[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, frame.index.sort_values())
tm.assert_index_equal(joined.columns, expected_columns)
tm.assert_raises_regex(
ValueError, 'join method', f.join, f2, how='foo')
# corner case - overlapping columns
for how in ('outer', 'left', 'inner'):
with tm.assert_raises_regex(ValueError, 'columns overlap but '
'no suffix'):
frame.join(frame, how=how)
def test_join_index_more(frame):
af = frame.loc[:, ['A', 'B']]
bf = frame.loc[::2, ['C', 'D']]
expected = af.copy()
expected['C'] = frame['C'][::2]
expected['D'] = 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(frame):
df = frame.copy()
s = df.pop(frame.columns[-1])
joined = df.join(s)
# TODO should this check_names ?
tm.assert_frame_equal(joined, frame, check_names=False)
s.name = None
tm.assert_raises_regex(ValueError, 'must have a name', df.join, s)
def test_join_overlap(frame):
df1 = frame.loc[:, ['A', 'B', 'C']]
df2 = 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 = 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 x: '{key}{key}'.format(key=x))
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)