Inzynierka/Lib/site-packages/pandas/tests/indexes/datetimes/test_partial_slicing.py
2023-06-02 12:51:02 +02:00

458 lines
16 KiB
Python

""" test partial slicing on Series/Frame """
from datetime import datetime
import numpy as np
import pytest
from pandas import (
DataFrame,
DatetimeIndex,
Index,
Series,
Timedelta,
Timestamp,
date_range,
)
import pandas._testing as tm
class TestSlicing:
def test_string_index_series_name_converted(self):
# GH#1644
df = DataFrame(np.random.randn(10, 4), index=date_range("1/1/2000", periods=10))
result = df.loc["1/3/2000"]
assert result.name == df.index[2]
result = df.T["1/3/2000"]
assert result.name == df.index[2]
def test_stringified_slice_with_tz(self):
# GH#2658
start = "2013-01-07"
idx = date_range(start=start, freq="1d", periods=10, tz="US/Eastern")
df = DataFrame(np.arange(10), index=idx)
df["2013-01-14 23:44:34.437768-05:00":] # no exception here
def test_return_type_doesnt_depend_on_monotonicity(self):
# GH#24892 we get Series back regardless of whether our DTI is monotonic
dti = date_range(start="2015-5-13 23:59:00", freq="min", periods=3)
ser = Series(range(3), index=dti)
# non-monotonic index
ser2 = Series(range(3), index=[dti[1], dti[0], dti[2]])
# key with resolution strictly lower than "min"
key = "2015-5-14 00"
# monotonic increasing index
result = ser.loc[key]
expected = ser.iloc[1:]
tm.assert_series_equal(result, expected)
# monotonic decreasing index
result = ser.iloc[::-1].loc[key]
expected = ser.iloc[::-1][:-1]
tm.assert_series_equal(result, expected)
# non-monotonic index
result2 = ser2.loc[key]
expected2 = ser2.iloc[::2]
tm.assert_series_equal(result2, expected2)
def test_return_type_doesnt_depend_on_monotonicity_higher_reso(self):
# GH#24892 we get Series back regardless of whether our DTI is monotonic
dti = date_range(start="2015-5-13 23:59:00", freq="min", periods=3)
ser = Series(range(3), index=dti)
# non-monotonic index
ser2 = Series(range(3), index=[dti[1], dti[0], dti[2]])
# key with resolution strictly *higher) than "min"
key = "2015-5-14 00:00:00"
# monotonic increasing index
result = ser.loc[key]
assert result == 1
# monotonic decreasing index
result = ser.iloc[::-1].loc[key]
assert result == 1
# non-monotonic index
result2 = ser2.loc[key]
assert result2 == 0
def test_monotone_DTI_indexing_bug(self):
# GH 19362
# Testing accessing the first element in a monotonic descending
# partial string indexing.
df = DataFrame(list(range(5)))
date_list = [
"2018-01-02",
"2017-02-10",
"2016-03-10",
"2015-03-15",
"2014-03-16",
]
date_index = DatetimeIndex(date_list)
df["date"] = date_index
expected = DataFrame({0: list(range(5)), "date": date_index})
tm.assert_frame_equal(df, expected)
# We get a slice because df.index's resolution is hourly and we
# are slicing with a daily-resolution string. If both were daily,
# we would get a single item back
dti = date_range("20170101 01:00:00", periods=3)
df = DataFrame({"A": [1, 2, 3]}, index=dti[::-1])
expected = DataFrame({"A": 1}, index=dti[-1:][::-1])
result = df.loc["2017-01-03"]
tm.assert_frame_equal(result, expected)
result2 = df.iloc[::-1].loc["2017-01-03"]
expected2 = expected.iloc[::-1]
tm.assert_frame_equal(result2, expected2)
def test_slice_year(self):
dti = date_range(freq="B", start=datetime(2005, 1, 1), periods=500)
s = Series(np.arange(len(dti)), index=dti)
result = s["2005"]
expected = s[s.index.year == 2005]
tm.assert_series_equal(result, expected)
df = DataFrame(np.random.rand(len(dti), 5), index=dti)
result = df.loc["2005"]
expected = df[df.index.year == 2005]
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"partial_dtime",
[
"2019",
"2019Q4",
"Dec 2019",
"2019-12-31",
"2019-12-31 23",
"2019-12-31 23:59",
],
)
def test_slice_end_of_period_resolution(self, partial_dtime):
# GH#31064
dti = date_range("2019-12-31 23:59:55.999999999", periods=10, freq="s")
ser = Series(range(10), index=dti)
result = ser[partial_dtime]
expected = ser.iloc[:5]
tm.assert_series_equal(result, expected)
def test_slice_quarter(self):
dti = date_range(freq="D", start=datetime(2000, 6, 1), periods=500)
s = Series(np.arange(len(dti)), index=dti)
assert len(s["2001Q1"]) == 90
df = DataFrame(np.random.rand(len(dti), 5), index=dti)
assert len(df.loc["1Q01"]) == 90
def test_slice_month(self):
dti = date_range(freq="D", start=datetime(2005, 1, 1), periods=500)
s = Series(np.arange(len(dti)), index=dti)
assert len(s["2005-11"]) == 30
df = DataFrame(np.random.rand(len(dti), 5), index=dti)
assert len(df.loc["2005-11"]) == 30
tm.assert_series_equal(s["2005-11"], s["11-2005"])
def test_partial_slice(self):
rng = date_range(freq="D", start=datetime(2005, 1, 1), periods=500)
s = Series(np.arange(len(rng)), index=rng)
result = s["2005-05":"2006-02"]
expected = s["20050501":"20060228"]
tm.assert_series_equal(result, expected)
result = s["2005-05":]
expected = s["20050501":]
tm.assert_series_equal(result, expected)
result = s[:"2006-02"]
expected = s[:"20060228"]
tm.assert_series_equal(result, expected)
result = s["2005-1-1"]
assert result == s.iloc[0]
with pytest.raises(KeyError, match=r"^'2004-12-31'$"):
s["2004-12-31"]
def test_partial_slice_daily(self):
rng = date_range(freq="H", start=datetime(2005, 1, 31), periods=500)
s = Series(np.arange(len(rng)), index=rng)
result = s["2005-1-31"]
tm.assert_series_equal(result, s.iloc[:24])
with pytest.raises(KeyError, match=r"^'2004-12-31 00'$"):
s["2004-12-31 00"]
def test_partial_slice_hourly(self):
rng = date_range(freq="T", start=datetime(2005, 1, 1, 20, 0, 0), periods=500)
s = Series(np.arange(len(rng)), index=rng)
result = s["2005-1-1"]
tm.assert_series_equal(result, s.iloc[: 60 * 4])
result = s["2005-1-1 20"]
tm.assert_series_equal(result, s.iloc[:60])
assert s["2005-1-1 20:00"] == s.iloc[0]
with pytest.raises(KeyError, match=r"^'2004-12-31 00:15'$"):
s["2004-12-31 00:15"]
def test_partial_slice_minutely(self):
rng = date_range(freq="S", start=datetime(2005, 1, 1, 23, 59, 0), periods=500)
s = Series(np.arange(len(rng)), index=rng)
result = s["2005-1-1 23:59"]
tm.assert_series_equal(result, s.iloc[:60])
result = s["2005-1-1"]
tm.assert_series_equal(result, s.iloc[:60])
assert s[Timestamp("2005-1-1 23:59:00")] == s.iloc[0]
with pytest.raises(KeyError, match=r"^'2004-12-31 00:00:00'$"):
s["2004-12-31 00:00:00"]
def test_partial_slice_second_precision(self):
rng = date_range(
start=datetime(2005, 1, 1, 0, 0, 59, microsecond=999990),
periods=20,
freq="US",
)
s = Series(np.arange(20), rng)
tm.assert_series_equal(s["2005-1-1 00:00"], s.iloc[:10])
tm.assert_series_equal(s["2005-1-1 00:00:59"], s.iloc[:10])
tm.assert_series_equal(s["2005-1-1 00:01"], s.iloc[10:])
tm.assert_series_equal(s["2005-1-1 00:01:00"], s.iloc[10:])
assert s[Timestamp("2005-1-1 00:00:59.999990")] == s.iloc[0]
with pytest.raises(KeyError, match="2005-1-1 00:00:00"):
s["2005-1-1 00:00:00"]
def test_partial_slicing_dataframe(self):
# GH14856
# Test various combinations of string slicing resolution vs.
# index resolution
# - If string resolution is less precise than index resolution,
# string is considered a slice
# - If string resolution is equal to or more precise than index
# resolution, string is considered an exact match
formats = [
"%Y",
"%Y-%m",
"%Y-%m-%d",
"%Y-%m-%d %H",
"%Y-%m-%d %H:%M",
"%Y-%m-%d %H:%M:%S",
]
resolutions = ["year", "month", "day", "hour", "minute", "second"]
for rnum, resolution in enumerate(resolutions[2:], 2):
# we check only 'day', 'hour', 'minute' and 'second'
unit = Timedelta("1 " + resolution)
middate = datetime(2012, 1, 1, 0, 0, 0)
index = DatetimeIndex([middate - unit, middate, middate + unit])
values = [1, 2, 3]
df = DataFrame({"a": values}, index, dtype=np.int64)
assert df.index.resolution == resolution
# Timestamp with the same resolution as index
# Should be exact match for Series (return scalar)
# and raise KeyError for Frame
for timestamp, expected in zip(index, values):
ts_string = timestamp.strftime(formats[rnum])
# make ts_string as precise as index
result = df["a"][ts_string]
assert isinstance(result, np.int64)
assert result == expected
msg = rf"^'{ts_string}'$"
with pytest.raises(KeyError, match=msg):
df[ts_string]
# Timestamp with resolution less precise than index
for fmt in formats[:rnum]:
for element, theslice in [[0, slice(None, 1)], [1, slice(1, None)]]:
ts_string = index[element].strftime(fmt)
# Series should return slice
result = df["a"][ts_string]
expected = df["a"][theslice]
tm.assert_series_equal(result, expected)
# pre-2.0 df[ts_string] was overloaded to interpret this
# as slicing along index
with pytest.raises(KeyError, match=ts_string):
df[ts_string]
# Timestamp with resolution more precise than index
# Compatible with existing key
# Should return scalar for Series
# and raise KeyError for Frame
for fmt in formats[rnum + 1 :]:
ts_string = index[1].strftime(fmt)
result = df["a"][ts_string]
assert isinstance(result, np.int64)
assert result == 2
msg = rf"^'{ts_string}'$"
with pytest.raises(KeyError, match=msg):
df[ts_string]
# Not compatible with existing key
# Should raise KeyError
for fmt, res in list(zip(formats, resolutions))[rnum + 1 :]:
ts = index[1] + Timedelta("1 " + res)
ts_string = ts.strftime(fmt)
msg = rf"^'{ts_string}'$"
with pytest.raises(KeyError, match=msg):
df["a"][ts_string]
with pytest.raises(KeyError, match=msg):
df[ts_string]
def test_partial_slicing_with_multiindex(self):
# GH 4758
# partial string indexing with a multi-index buggy
df = DataFrame(
{
"ACCOUNT": ["ACCT1", "ACCT1", "ACCT1", "ACCT2"],
"TICKER": ["ABC", "MNP", "XYZ", "XYZ"],
"val": [1, 2, 3, 4],
},
index=date_range("2013-06-19 09:30:00", periods=4, freq="5T"),
)
df_multi = df.set_index(["ACCOUNT", "TICKER"], append=True)
expected = DataFrame(
[[1]], index=Index(["ABC"], name="TICKER"), columns=["val"]
)
result = df_multi.loc[("2013-06-19 09:30:00", "ACCT1")]
tm.assert_frame_equal(result, expected)
expected = df_multi.loc[
(Timestamp("2013-06-19 09:30:00", tz=None), "ACCT1", "ABC")
]
result = df_multi.loc[("2013-06-19 09:30:00", "ACCT1", "ABC")]
tm.assert_series_equal(result, expected)
# partial string indexing on first level, scalar indexing on the other two
result = df_multi.loc[("2013-06-19", "ACCT1", "ABC")]
expected = df_multi.iloc[:1].droplevel([1, 2])
tm.assert_frame_equal(result, expected)
def test_partial_slicing_with_multiindex_series(self):
# GH 4294
# partial slice on a series mi
ser = DataFrame(
np.random.rand(1000, 1000), index=date_range("2000-1-1", periods=1000)
).stack()
s2 = ser[:-1].copy()
expected = s2["2000-1-4"]
result = s2[Timestamp("2000-1-4")]
tm.assert_series_equal(result, expected)
result = ser[Timestamp("2000-1-4")]
expected = ser["2000-1-4"]
tm.assert_series_equal(result, expected)
df2 = DataFrame(ser)
expected = df2.xs("2000-1-4")
result = df2.loc[Timestamp("2000-1-4")]
tm.assert_frame_equal(result, expected)
def test_partial_slice_requires_monotonicity(self):
# Disallowed since 2.0 (GH 37819)
ser = Series(np.arange(10), date_range("2014-01-01", periods=10))
nonmonotonic = ser[[3, 5, 4]]
timestamp = Timestamp("2014-01-10")
with pytest.raises(
KeyError, match="Value based partial slicing on non-monotonic"
):
nonmonotonic["2014-01-10":]
with pytest.raises(KeyError, match=r"Timestamp\('2014-01-10 00:00:00'\)"):
nonmonotonic[timestamp:]
with pytest.raises(
KeyError, match="Value based partial slicing on non-monotonic"
):
nonmonotonic.loc["2014-01-10":]
with pytest.raises(KeyError, match=r"Timestamp\('2014-01-10 00:00:00'\)"):
nonmonotonic.loc[timestamp:]
def test_loc_datetime_length_one(self):
# GH16071
df = DataFrame(
columns=["1"],
index=date_range("2016-10-01T00:00:00", "2016-10-01T23:59:59"),
)
result = df.loc[datetime(2016, 10, 1) :]
tm.assert_frame_equal(result, df)
result = df.loc["2016-10-01T00:00:00":]
tm.assert_frame_equal(result, df)
@pytest.mark.parametrize(
"start",
[
"2018-12-02 21:50:00+00:00",
Timestamp("2018-12-02 21:50:00+00:00"),
Timestamp("2018-12-02 21:50:00+00:00").to_pydatetime(),
],
)
@pytest.mark.parametrize(
"end",
[
"2018-12-02 21:52:00+00:00",
Timestamp("2018-12-02 21:52:00+00:00"),
Timestamp("2018-12-02 21:52:00+00:00").to_pydatetime(),
],
)
def test_getitem_with_datestring_with_UTC_offset(self, start, end):
# GH 24076
idx = date_range(
start="2018-12-02 14:50:00-07:00",
end="2018-12-02 14:50:00-07:00",
freq="1min",
)
df = DataFrame(1, index=idx, columns=["A"])
result = df[start:end]
expected = df.iloc[0:3, :]
tm.assert_frame_equal(result, expected)
# GH 16785
start = str(start)
end = str(end)
with pytest.raises(ValueError, match="Both dates must"):
df[start : end[:-4] + "1:00"]
with pytest.raises(ValueError, match="The index must be timezone"):
df = df.tz_localize(None)
df[start:end]
def test_slice_reduce_to_series(self):
# GH 27516
df = DataFrame({"A": range(24)}, index=date_range("2000", periods=24, freq="M"))
expected = Series(
range(12), index=date_range("2000", periods=12, freq="M"), name="A"
)
result = df.loc["2000", "A"]
tm.assert_series_equal(result, expected)