1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
""" 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)