Esempio n. 1
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 def test_astype_object(self, tz_naive_fixture):
     tz = tz_naive_fixture
     dti = pd.date_range('2016-01-01', periods=3, tz=tz)
     arr = DatetimeArray(dti)
     asobj = arr.astype('O')
     assert isinstance(asobj, np.ndarray)
     assert asobj.dtype == 'O'
     assert list(asobj) == list(dti)
Esempio n. 2
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    def test_repeat_preserves_tz(self):
        dti = pd.date_range('2000', periods=2, freq='D', tz='US/Central')
        arr = DatetimeArray(dti)

        repeated = arr.repeat([1, 1])

        # preserves tz and values, but not freq
        expected = DatetimeArray(arr.asi8, freq=None, tz=arr.tz)
        tm.assert_equal(repeated, expected)
Esempio n. 3
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    def test_to_period(self, datetime_index, freqstr):
        dti = datetime_index
        arr = DatetimeArrayMixin(dti)

        expected = dti.to_period(freq=freqstr)
        result = arr.to_period(freq=freqstr)
        assert isinstance(result, PeriodArrayMixin)

        # placeholder until these become actual EA subclasses and we can use
        #  an EA-specific tm.assert_ function
        tm.assert_index_equal(pd.Index(result), pd.Index(expected))
Esempio n. 4
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    def test_to_period(self, datetime_index, freqstr):
        dti = datetime_index
        arr = DatetimeArray(dti)

        expected = dti.to_period(freq=freqstr)
        result = arr.to_period(freq=freqstr)
        assert isinstance(result, PeriodArray)

        # placeholder until these become actual EA subclasses and we can use
        #  an EA-specific tm.assert_ function
        tm.assert_index_equal(pd.Index(result), pd.Index(expected))
Esempio n. 5
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    def test_concat_same_type_invalid(self, datetime_index):
        # different timezones
        dti = datetime_index
        arr = DatetimeArray(dti)

        if arr.tz is None:
            other = arr.tz_localize('UTC')
        else:
            other = arr.tz_localize(None)

        with pytest.raises(AssertionError):
            arr._concat_same_type([arr, other])
Esempio n. 6
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    def test_concat_same_type_invalid(self, datetime_index):
        # different timezones
        dti = datetime_index
        arr = DatetimeArray(dti)

        if arr.tz is None:
            other = arr.tz_localize('UTC')
        else:
            other = arr.tz_localize(None)

        with pytest.raises(AssertionError):
            arr._concat_same_type([arr, other])
Esempio n. 7
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    def test_value_counts_preserves_tz(self):
        dti = pd.date_range('2000', periods=2, freq='D', tz='US/Central')
        arr = DatetimeArray(dti).repeat([4, 3])

        result = arr.value_counts()

        # Note: not tm.assert_index_equal, since `freq`s do not match
        assert result.index.equals(dti)

        arr[-2] = pd.NaT
        result = arr.value_counts()
        expected = pd.Series([1, 4, 2], index=[pd.NaT, dti[0], dti[1]])
        tm.assert_series_equal(result, expected)
Esempio n. 8
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    def _ensure_localized(self, arg, ambiguous='raise', nonexistent='raise',
                          from_utc=False):
        # See DatetimeLikeArrayMixin._ensure_localized.__doc__

        if getattr(self, 'tz', None):
            # ensure_localized is only relevant for tz-aware DTI
            from pandas.core.arrays import DatetimeArrayMixin as DatetimeArray
            dtarr = DatetimeArray(self)
            result = dtarr._ensure_localized(arg,
                                             ambiguous=ambiguous,
                                             nonexistent=nonexistent,
                                             from_utc=from_utc)
            return type(self)(result, name=self.name)
        return arg
Esempio n. 9
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    def _ensure_localized(self, arg, ambiguous='raise', nonexistent='raise',
                          from_utc=False):
        # See DatetimeLikeArrayMixin._ensure_localized.__doc__

        if getattr(self, 'tz', None):
            # ensure_localized is only relevant for tz-aware DTI
            from pandas.core.arrays import DatetimeArrayMixin as DatetimeArray
            dtarr = DatetimeArray(self)
            result = dtarr._ensure_localized(arg,
                                             ambiguous=ambiguous,
                                             nonexistent=nonexistent,
                                             from_utc=from_utc)
            return type(self)(result, name=self.name)
        return arg
Esempio n. 10
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    def test_value_counts_preserves_tz(self):
        dti = pd.date_range('2000', periods=2, freq='D', tz='US/Central')
        arr = DatetimeArray(dti).repeat([4, 3])

        result = arr.value_counts()

        # Note: not tm.assert_index_equal, since `freq`s do not match
        assert result.index.equals(dti)

        arr[-2] = pd.NaT
        result = arr.value_counts()
        expected = pd.Series([1, 4, 2],
                             index=[pd.NaT, dti[0], dti[1]])
        tm.assert_series_equal(result, expected)
Esempio n. 11
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    def test_fillna_preserves_tz(self, method):
        dti = pd.date_range('2000-01-01', periods=5, freq='D', tz='US/Central')
        arr = DatetimeArray(dti, copy=True)
        arr[2] = pd.NaT

        fill_val = dti[1] if method == 'pad' else dti[3]
        expected = DatetimeArray([dti[0], dti[1], fill_val, dti[3], dti[4]],
                                 freq=None, tz='US/Central')

        result = arr.fillna(method=method)
        tm.assert_extension_array_equal(result, expected)

        # assert that arr and dti were not modified in-place
        assert arr[2] is pd.NaT
        assert dti[2] == pd.Timestamp('2000-01-03', tz='US/Central')
Esempio n. 12
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    def test_min_max_empty(self, skipna, tz):
        arr = DatetimeArray._from_sequence([], tz=tz)
        result = arr.min(skipna=skipna)
        assert result is pd.NaT

        result = arr.max(skipna=skipna)
        assert result is pd.NaT
Esempio n. 13
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    def test_from_pandas_array(self):
        arr = pd.array(np.arange(5, dtype=np.int64)) * 3600 * 10**9

        result = DatetimeArray._from_sequence(arr, freq='infer')

        expected = pd.date_range('1970-01-01', periods=5, freq='H')._eadata
        tm.assert_datetime_array_equal(result, expected)
Esempio n. 14
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    def test_min_max_empty(self, skipna, tz):
        arr = DatetimeArray._from_sequence([], tz=tz)
        result = arr.min(skipna=skipna)
        assert result is pd.NaT

        result = arr.max(skipna=skipna)
        assert result is pd.NaT
Esempio n. 15
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    def _add_datetimelike_scalar(self, other):
        # adding a timedeltaindex to a datetimelike
        from pandas.core.arrays import DatetimeArrayMixin

        assert other is not NaT
        other = Timestamp(other)
        if other is NaT:
            # In this case we specifically interpret NaT as a datetime, not
            # the timedelta interpretation we would get by returning self + NaT
            result = self.asi8.view('m8[ms]') + NaT.to_datetime64()
            return DatetimeArrayMixin(result)

        i8 = self.asi8
        result = checked_add_with_arr(i8, other.value, arr_mask=self._isnan)
        result = self._maybe_mask_results(result)
        return DatetimeArrayMixin(result, tz=other.tz, freq=self.freq)
Esempio n. 16
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    def test_unstack(self, obj):
        # GH-13287: can't use base test, since building the expected fails.
        data = DatetimeArray._from_sequence(['2000', '2001', '2002', '2003'],
                                            tz='US/Central')
        index = pd.MultiIndex.from_product(([['A', 'B'], ['a', 'b']]),
                                           names=['a', 'b'])

        if obj == "series":
            ser = pd.Series(data, index=index)
            expected = pd.DataFrame(
                {
                    "A": data.take([0, 1]),
                    "B": data.take([2, 3])
                },
                index=pd.Index(['a', 'b'], name='b'))
            expected.columns.name = 'a'

        else:
            ser = pd.DataFrame({"A": data, "B": data}, index=index)
            expected = pd.DataFrame(
                {
                    ("A", "A"): data.take([0, 1]),
                    ("A", "B"): data.take([2, 3]),
                    ("B", "A"): data.take([0, 1]),
                    ("B", "B"): data.take([2, 3])
                },
                index=pd.Index(['a', 'b'], name='b'))
            expected.columns.names = [None, 'a']

        result = ser.unstack(0)
        self.assert_equal(result, expected)
Esempio n. 17
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    def test_int_properties(self, datetime_index, propname):
        dti = datetime_index
        arr = DatetimeArrayMixin(dti)

        result = getattr(arr, propname)
        expected = np.array(getattr(dti, propname), dtype=result.dtype)

        tm.assert_numpy_array_equal(result, expected)
Esempio n. 18
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 def _add_datelike(self, other):
     # adding a timedeltaindex to a datetimelike
     from pandas.core.arrays import DatetimeArrayMixin
     if isinstance(other, (DatetimeArrayMixin, np.ndarray)):
         # if other is an ndarray, we assume it is datetime64-dtype
         # defer to implementation in DatetimeIndex
         if not isinstance(other, DatetimeArrayMixin):
             other = DatetimeArrayMixin(other)
         return other + self
     else:
         assert other is not NaT
         other = Timestamp(other)
         i8 = self.asi8
         result = checked_add_with_arr(i8, other.value,
                                       arr_mask=self._isnan)
         result = self._maybe_mask_results(result, fill_value=iNaT)
         return DatetimeArrayMixin(result)
Esempio n. 19
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    def _add_datetime_arraylike(self, other):
        """Add DatetimeArray/Index or ndarray[datetime64] to TimedeltaArray"""
        if isinstance(other, np.ndarray):
            # At this point we have already checked that dtype is datetime64
            from pandas.core.arrays import DatetimeArrayMixin
            other = DatetimeArrayMixin(other)

        # defer to implementation in DatetimeArray
        return other + self
Esempio n. 20
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    def test_bool_properties(self, datetime_index, propname):
        # in this case _bool_ops is just `is_leap_year`
        dti = datetime_index
        arr = DatetimeArrayMixin(dti)
        assert dti.freq == arr.freq

        result = getattr(arr, propname)
        expected = np.array(getattr(dti, propname), dtype=result.dtype)

        tm.assert_numpy_array_equal(result, expected)
Esempio n. 21
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    def test_from_dti(self, tz_naive_fixture):
        tz = tz_naive_fixture
        dti = pd.date_range('2016-01-01', periods=3, tz=tz)
        arr = DatetimeArrayMixin(dti)
        assert list(dti) == list(arr)

        # Check that Index.__new__ knows what to do with DatetimeArray
        dti2 = pd.Index(arr)
        assert isinstance(dti2, pd.DatetimeIndex)
        assert list(dti2) == list(arr)
Esempio n. 22
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    def test_to_timestamp(self, how, period_index):
        pi = period_index
        arr = PeriodArrayMixin(pi)

        expected = DatetimeArrayMixin(pi.to_timestamp(how=how))
        result = arr.to_timestamp(how=how)
        assert isinstance(result, DatetimeArrayMixin)

        # placeholder until these become actual EA subclasses and we can use
        #  an EA-specific tm.assert_ function
        tm.assert_index_equal(pd.Index(result), pd.Index(expected))
Esempio n. 23
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    def test_astype_int(self, dtype):
        arr = DatetimeArray._from_sequence(
            [pd.Timestamp('2000'), pd.Timestamp('2001')])
        result = arr.astype(dtype)

        if np.dtype(dtype).kind == 'u':
            expected_dtype = np.dtype('uint64')
        else:
            expected_dtype = np.dtype('int64')
        expected = arr.astype(expected_dtype)

        assert result.dtype == expected_dtype
        tm.assert_numpy_array_equal(result, expected)
Esempio n. 24
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    def test_astype_int(self, dtype):
        arr = DatetimeArray._from_sequence([pd.Timestamp('2000'),
                                            pd.Timestamp('2001')])
        result = arr.astype(dtype)

        if np.dtype(dtype).kind == 'u':
            expected_dtype = np.dtype('uint64')
        else:
            expected_dtype = np.dtype('int64')
        expected = arr.astype(expected_dtype)

        assert result.dtype == expected_dtype
        tm.assert_numpy_array_equal(result, expected)
Esempio n. 25
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    def test_concat_same_type_different_freq(self):
        # we *can* concatentate DTI with different freqs.
        a = DatetimeArray(pd.date_range('2000', periods=2, freq='D',
                                        tz='US/Central'))
        b = DatetimeArray(pd.date_range('2000', periods=2, freq='H',
                                        tz='US/Central'))
        result = DatetimeArray._concat_same_type([a, b])
        expected = DatetimeArray(pd.to_datetime([
            '2000-01-01 00:00:00', '2000-01-02 00:00:00',
            '2000-01-01 00:00:00', '2000-01-01 01:00:00',
        ]).tz_localize("US/Central"))

        tm.assert_datetime_array_equal(result, expected)
Esempio n. 26
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    def test_concat_same_type_different_freq(self):
        # we *can* concatentate DTI with different freqs.
        a = DatetimeArray(pd.date_range('2000', periods=2, freq='D',
                                        tz='US/Central'))
        b = DatetimeArray(pd.date_range('2000', periods=2, freq='H',
                                        tz='US/Central'))
        result = DatetimeArray._concat_same_type([a, b])
        expected = DatetimeArray(pd.to_datetime([
            '2000-01-01 00:00:00', '2000-01-02 00:00:00',
            '2000-01-01 00:00:00', '2000-01-01 01:00:00',
        ]).tz_localize("US/Central"))

        tm.assert_datetime_array_equal(result, expected)
Esempio n. 27
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    def test_array(self, tz_naive_fixture):
        # GH#23524
        tz = tz_naive_fixture
        dti = pd.date_range('2016-01-01', periods=3, tz=tz)
        arr = DatetimeArrayMixin(dti)

        expected = dti.asi8.view('M8[ns]')
        result = np.array(arr)
        tm.assert_numpy_array_equal(result, expected)

        # check that we are not making copies when setting copy=False
        result = np.array(arr, copy=False)
        assert result.base is expected.base
        assert result.base is not None
Esempio n. 28
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    def test_array_object_dtype(self, tz_naive_fixture):
        # GH#23524
        tz = tz_naive_fixture
        dti = pd.date_range('2016-01-01', periods=3, tz=tz)
        arr = DatetimeArrayMixin(dti)

        expected = np.array(list(dti))

        result = np.array(arr, dtype=object)
        tm.assert_numpy_array_equal(result, expected)

        # also test the DatetimeIndex method while we're at it
        result = np.array(dti, dtype=object)
        tm.assert_numpy_array_equal(result, expected)
Esempio n. 29
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 def __rsub__(self, other):
     if is_datetime64_dtype(other) and is_timedelta64_dtype(self):
         # ndarray[datetime64] cannot be subtracted from self, so
         # we need to wrap in DatetimeArray/Index and flip the operation
         if not isinstance(other, DatetimeLikeArrayMixin):
             # Avoid down-casting DatetimeIndex
             from pandas.core.arrays import DatetimeArrayMixin
             other = DatetimeArrayMixin(other)
         return other - self
     elif (is_datetime64_any_dtype(self) and hasattr(other, 'dtype')
           and not is_datetime64_any_dtype(other)):
         # GH#19959 datetime - datetime is well-defined as timedelta,
         # but any other type - datetime is not well-defined.
         raise TypeError("cannot subtract {cls} from {typ}".format(
             cls=type(self).__name__, typ=type(other).__name__))
     return -(self - other)
Esempio n. 30
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    def test_take_fill_valid(self, datetime_index, tz_naive_fixture):
        dti = datetime_index.tz_localize(tz_naive_fixture)
        arr = DatetimeArray(dti)

        now = pd.Timestamp.now().tz_localize(dti.tz)
        result = arr.take([-1, 1], allow_fill=True, fill_value=now)
        assert result[0] == now

        with pytest.raises(ValueError):
            # fill_value Timedelta invalid
            arr.take([-1, 1], allow_fill=True, fill_value=now - now)

        with pytest.raises(ValueError):
            # fill_value Period invalid
            arr.take([-1, 1], allow_fill=True, fill_value=pd.Period('2014Q1'))

        tz = None if dti.tz is not None else 'US/Eastern'
        now = pd.Timestamp.now().tz_localize(tz)
        with pytest.raises(TypeError):
            # Timestamp with mismatched tz-awareness
            arr.take([-1, 1], allow_fill=True, fill_value=now)
Esempio n. 31
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    def test_take_fill_valid(self, datetime_index, tz_naive_fixture):
        dti = datetime_index.tz_localize(tz_naive_fixture)
        arr = DatetimeArray(dti)

        now = pd.Timestamp.now().tz_localize(dti.tz)
        result = arr.take([-1, 1], allow_fill=True, fill_value=now)
        assert result[0] == now

        with pytest.raises(ValueError):
            # fill_value Timedelta invalid
            arr.take([-1, 1], allow_fill=True, fill_value=now - now)

        with pytest.raises(ValueError):
            # fill_value Period invalid
            arr.take([-1, 1], allow_fill=True, fill_value=pd.Period('2014Q1'))

        tz = None if dti.tz is not None else 'US/Eastern'
        now = pd.Timestamp.now().tz_localize(tz)
        with pytest.raises(TypeError):
            # Timestamp with mismatched tz-awareness
            arr.take([-1, 1], allow_fill=True, fill_value=now)
Esempio n. 32
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    def to_timestamp(self, freq=None, how='start'):
        """
        Cast to DatetimeArray/Index

        Parameters
        ----------
        freq : string or DateOffset, optional
            Target frequency. The default is 'D' for week or longer,
            'S' otherwise
        how : {'s', 'e', 'start', 'end'}

        Returns
        -------
        DatetimeArray/Index
        """
        from pandas.core.arrays import DatetimeArrayMixin

        how = libperiod._validate_end_alias(how)

        end = how == 'E'
        if end:
            if freq == 'B':
                # roll forward to ensure we land on B date
                adjust = Timedelta(1, 'D') - Timedelta(1, 'ns')
                return self.to_timestamp(how='start') + adjust
            else:
                adjust = Timedelta(1, 'ns')
                return (self + 1).to_timestamp(how='start') - adjust

        if freq is None:
            base, mult = frequencies.get_freq_code(self.freq)
            freq = frequencies.get_to_timestamp_base(base)
        else:
            freq = Period._maybe_convert_freq(freq)

        base, mult = frequencies.get_freq_code(freq)
        new_data = self.asfreq(freq, how=how)

        new_data = libperiod.periodarr_to_dt64arr(new_data._ndarray_values,
                                                  base)
        return DatetimeArrayMixin(new_data, freq='infer')
Esempio n. 33
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    def to_timestamp(self, freq=None, how='start'):
        """
        Cast to DatetimeArray/Index.

        Parameters
        ----------
        freq : string or DateOffset, optional
            Target frequency. The default is 'D' for week or longer,
            'S' otherwise
        how : {'s', 'e', 'start', 'end'}

        Returns
        -------
        DatetimeArray/Index
        """
        from pandas.core.arrays import DatetimeArrayMixin

        how = libperiod._validate_end_alias(how)

        end = how == 'E'
        if end:
            if freq == 'B':
                # roll forward to ensure we land on B date
                adjust = Timedelta(1, 'D') - Timedelta(1, 'ns')
                return self.to_timestamp(how='start') + adjust
            else:
                adjust = Timedelta(1, 'ns')
                return (self + self.freq).to_timestamp(how='start') - adjust

        if freq is None:
            base, mult = frequencies.get_freq_code(self.freq)
            freq = frequencies.get_to_timestamp_base(base)
        else:
            freq = Period._maybe_convert_freq(freq)

        base, mult = frequencies.get_freq_code(freq)
        new_data = self.asfreq(freq, how=how)

        new_data = libperiod.periodarr_to_dt64arr(new_data.asi8, base)
        return DatetimeArrayMixin._from_sequence(new_data, freq='infer')
Esempio n. 34
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    def test_min_max(self, tz):
        arr = DatetimeArray._from_sequence([
            '2000-01-03',
            '2000-01-03',
            'NaT',
            '2000-01-02',
            '2000-01-05',
            '2000-01-04',
        ], tz=tz)

        result = arr.min()
        expected = pd.Timestamp('2000-01-02', tz=tz)
        assert result == expected

        result = arr.max()
        expected = pd.Timestamp('2000-01-05', tz=tz)
        assert result == expected

        result = arr.min(skipna=False)
        assert result is pd.NaT

        result = arr.max(skipna=False)
        assert result is pd.NaT
Esempio n. 35
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    def test_min_max(self, tz):
        arr = DatetimeArray._from_sequence([
            '2000-01-03',
            '2000-01-03',
            'NaT',
            '2000-01-02',
            '2000-01-05',
            '2000-01-04',
        ], tz=tz)

        result = arr.min()
        expected = pd.Timestamp('2000-01-02', tz=tz)
        assert result == expected

        result = arr.max()
        expected = pd.Timestamp('2000-01-05', tz=tz)
        assert result == expected

        result = arr.min(skipna=False)
        assert result is pd.NaT

        result = arr.max(skipna=False)
        assert result is pd.NaT
Esempio n. 36
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 def test_tz_dtype_matches(self):
     arr = DatetimeArray._from_sequence(['2000'], tz='US/Central')
     result, _, _ = sequence_to_dt64ns(
         arr, dtype=DatetimeTZDtype(tz="US/Central"))
     tm.assert_numpy_array_equal(arr._data, result)
Esempio n. 37
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 def test_tz_dtype_mismatch_raises(self):
     arr = DatetimeArray._from_sequence(['2000'], tz='US/Central')
     with pytest.raises(TypeError, match='data is already tz-aware'):
         sequence_to_dt64ns(arr, dtype=DatetimeTZDtype(tz="UTC"))
Esempio n. 38
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 def test_tz_dtype_matches(self):
     arr = DatetimeArray._from_sequence(['2000'], tz='US/Central')
     result, _, _ = sequence_to_dt64ns(
         arr, dtype=DatetimeTZDtype(tz="US/Central"))
     tm.assert_numpy_array_equal(arr._data, result)
Esempio n. 39
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 def test_astype_to_same(self):
     arr = DatetimeArray._from_sequence(['2000'], tz='US/Central')
     result = arr.astype(DatetimeTZDtype(tz="US/Central"), copy=False)
     assert result is arr
Esempio n. 40
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 def test_tz_setter_raises(self):
     arr = DatetimeArray._from_sequence(['2000'], tz='US/Central')
     with pytest.raises(AttributeError, match='tz_localize'):
         arr.tz = 'UTC'
Esempio n. 41
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def array(data,         # type: Sequence[object]
          dtype=None,   # type: Optional[Union[str, np.dtype, ExtensionDtype]]
          copy=True,    # type: bool
          ):
    # type: (...) -> ExtensionArray
    """
    Create an array.

    .. versionadded:: 0.24.0

    Parameters
    ----------
    data : Sequence of objects
        The scalars inside `data` should be instances of the
        scalar type for `dtype`. It's expected that `data`
        represents a 1-dimensional array of data.

        When `data` is an Index or Series, the underlying array
        will be extracted from `data`.

    dtype : str, np.dtype, or ExtensionDtype, optional
        The dtype to use for the array. This may be a NumPy
        dtype or an extension type registered with pandas using
        :meth:`pandas.api.extensions.register_extension_dtype`.

        If not specified, there are two possibilities:

        1. When `data` is a :class:`Series`, :class:`Index`, or
           :class:`ExtensionArray`, the `dtype` will be taken
           from the data.
        2. Otherwise, pandas will attempt to infer the `dtype`
           from the data.

        Note that when `data` is a NumPy array, ``data.dtype`` is
        *not* used for inferring the array type. This is because
        NumPy cannot represent all the types of data that can be
        held in extension arrays.

        Currently, pandas will infer an extension dtype for sequences of

        ============================== =====================================
        scalar type                    Array Type
        =============================  =====================================
        * :class:`pandas.Interval`     :class:`pandas.IntervalArray`
        * :class:`pandas.Period`       :class:`pandas.arrays.PeriodArray`
        * :class:`datetime.datetime`   :class:`pandas.arrays.DatetimeArray`
        * :class:`datetime.timedelta`  :class:`pandas.arrays.TimedeltaArray`
        =============================  =====================================

        For all other cases, NumPy's usual inference rules will be used.

    copy : bool, default True
        Whether to copy the data, even if not necessary. Depending
        on the type of `data`, creating the new array may require
        copying data, even if ``copy=False``.

    Returns
    -------
    ExtensionArray
        The newly created array.

    Raises
    ------
    ValueError
        When `data` is not 1-dimensional.

    See Also
    --------
    numpy.array : Construct a NumPy array.
    arrays.PandasArray : ExtensionArray wrapping a NumPy array.
    Series : Construct a pandas Series.
    Index : Construct a pandas Index.

    Notes
    -----
    Omitting the `dtype` argument means pandas will attempt to infer the
    best array type from the values in the data. As new array types are
    added by pandas and 3rd party libraries, the "best" array type may
    change. We recommend specifying `dtype` to ensure that

    1. the correct array type for the data is returned
    2. the returned array type doesn't change as new extension types
       are added by pandas and third-party libraries

    Additionally, if the underlying memory representation of the returned
    array matters, we recommend specifying the `dtype` as a concrete object
    rather than a string alias or allowing it to be inferred. For example,
    a future version of pandas or a 3rd-party library may include a
    dedicated ExtensionArray for string data. In this event, the following
    would no longer return a :class:`arrays.PandasArray` backed by a NumPy
    array.

    >>> pd.array(['a', 'b'], dtype=str)
    <PandasArray>
    ['a', 'b']
    Length: 2, dtype: str32

    This would instead return the new ExtensionArray dedicated for string
    data. If you really need the new array to be backed by a  NumPy array,
    specify that in the dtype.

    >>> pd.array(['a', 'b'], dtype=np.dtype("<U1"))
    <PandasArray>
    ['a', 'b']
    Length: 2, dtype: str32

    Or use the dedicated constructor for the array you're expecting, and
    wrap that in a PandasArray

    >>> pd.array(np.array(['a', 'b'], dtype='<U1'))
    <PandasArray>
    ['a', 'b']
    Length: 2, dtype: str32

    Examples
    --------
    If a dtype is not specified, `data` is passed through to
    :meth:`numpy.array`, and a :class:`arrays.PandasArray` is returned.

    >>> pd.array([1, 2])
    <PandasArray>
    [1, 2]
    Length: 2, dtype: int64

    Or the NumPy dtype can be specified

    >>> pd.array([1, 2], dtype=np.dtype("int32"))
    <PandasArray>
    [1, 2]
    Length: 2, dtype: int32

    You can use the string alias for `dtype`

    >>> pd.array(['a', 'b', 'a'], dtype='category')
    [a, b, a]
    Categories (2, object): [a, b]

    Or specify the actual dtype

    >>> pd.array(['a', 'b', 'a'],
    ...          dtype=pd.CategoricalDtype(['a', 'b', 'c'], ordered=True))
    [a, b, a]
    Categories (3, object): [a < b < c]

    Because omitting the `dtype` passes the data through to NumPy,
    a mixture of valid integers and NA will return a floating-point
    NumPy array.

    >>> pd.array([1, 2, np.nan])
    <PandasArray>
    [1.0,  2.0, nan]
    Length: 3, dtype: float64

    To use pandas' nullable :class:`pandas.arrays.IntegerArray`, specify
    the dtype:

    >>> pd.array([1, 2, np.nan], dtype='Int64')
    <IntegerArray>
    [1, 2, NaN]
    Length: 3, dtype: Int64

    Pandas will infer an ExtensionArray for some types of data:

    >>> pd.array([pd.Period('2000', freq="D"), pd.Period("2000", freq="D")])
    <PeriodArray>
    ['2000-01-01', '2000-01-01']
    Length: 2, dtype: period[D]

    `data` must be 1-dimensional. A ValueError is raised when the input
    has the wrong dimensionality.

    >>> pd.array(1)
    Traceback (most recent call last):
      ...
    ValueError: Cannot pass scalar '1' to 'pandas.array'.
    """
    from pandas.core.arrays import (
        period_array, ExtensionArray, IntervalArray, PandasArray,
        DatetimeArrayMixin,
        TimedeltaArrayMixin,
    )
    from pandas.core.internals.arrays import extract_array

    if lib.is_scalar(data):
        msg = (
            "Cannot pass scalar '{}' to 'pandas.array'."
        )
        raise ValueError(msg.format(data))

    data = extract_array(data, extract_numpy=True)

    if dtype is None and isinstance(data, ExtensionArray):
        dtype = data.dtype

    # this returns None for not-found dtypes.
    if isinstance(dtype, compat.string_types):
        dtype = registry.find(dtype) or dtype

    if is_extension_array_dtype(dtype):
        cls = dtype.construct_array_type()
        return cls._from_sequence(data, dtype=dtype, copy=copy)

    if dtype is None:
        inferred_dtype = lib.infer_dtype(data)
        if inferred_dtype == 'period':
            try:
                return period_array(data, copy=copy)
            except tslibs.IncompatibleFrequency:
                # We may have a mixture of frequencies.
                # We choose to return an ndarray, rather than raising.
                pass
        elif inferred_dtype == 'interval':
            try:
                return IntervalArray(data, copy=copy)
            except ValueError:
                # We may have a mixture of `closed` here.
                # We choose to return an ndarray, rather than raising.
                pass

        elif inferred_dtype.startswith('datetime'):
            # datetime, datetime64
            try:
                return DatetimeArrayMixin._from_sequence(data, copy=copy)
            except ValueError:
                # Mixture of timezones, fall back to PandasArray
                pass

        elif inferred_dtype.startswith('timedelta'):
            # timedelta, timedelta64
            return TimedeltaArrayMixin._from_sequence(data, copy=copy)

        # TODO(BooleanArray): handle this type

    result = PandasArray._from_sequence(data, dtype=dtype, copy=copy)
    return result
Esempio n. 42
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 def test_tz_dtype_mismatch_raises(self):
     arr = DatetimeArray._from_sequence(['2000'], tz='US/Central')
     with pytest.raises(TypeError, match='data is already tz-aware'):
         sequence_to_dt64ns(arr, dtype=DatetimeTZDtype(tz="UTC"))
Esempio n. 43
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 def test_tz_setter_raises(self):
     arr = DatetimeArray._from_sequence(['2000'], tz='US/Central')
     with pytest.raises(AttributeError, match='tz_localize'):
         arr.tz = 'UTC'
Esempio n. 44
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 def test_astype_to_same(self):
     arr = DatetimeArray._from_sequence(['2000'], tz='US/Central')
     result = arr.astype(DatetimeTZDtype(tz="US/Central"), copy=False)
     assert result is arr