Exemple #1
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 def _parsed_string_to_bounds(self, reso, parsed):
     if reso == 'year':
         t1 = Period(year=parsed.year, freq='A')
     elif reso == 'month':
         t1 = Period(year=parsed.year, month=parsed.month, freq='M')
     elif reso == 'quarter':
         q = (parsed.month - 1) // 3 + 1
         t1 = Period(year=parsed.year, quarter=q, freq='Q-DEC')
     elif reso == 'day':
         t1 = Period(year=parsed.year, month=parsed.month, day=parsed.day,
                     freq='D')
     elif reso == 'hour':
         t1 = Period(year=parsed.year, month=parsed.month, day=parsed.day,
                     hour=parsed.hour, freq='H')
     elif reso == 'minute':
         t1 = Period(year=parsed.year, month=parsed.month, day=parsed.day,
                     hour=parsed.hour, minute=parsed.minute, freq='T')
     elif reso == 'second':
         t1 = Period(year=parsed.year, month=parsed.month, day=parsed.day,
                     hour=parsed.hour, minute=parsed.minute,
                     second=parsed.second, freq='S')
     else:
         raise KeyError(reso)
     return (t1.asfreq(self.freq, how='start'),
             t1.asfreq(self.freq, how='end'))
Exemple #2
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    def get_loc(self, key, method=None, tolerance=None):
        """
        Get integer location for requested label

        Returns
        -------
        loc : int
        """
        try:
            return self._engine.get_loc(key)
        except KeyError:
            if is_integer(key):
                raise

            try:
                asdt, parsed, reso = parse_time_string(key, self.freq)
                key = asdt
            except TypeError:
                pass

            try:
                key = Period(key, freq=self.freq)
            except ValueError:
                # we cannot construct the Period
                # as we have an invalid type
                raise KeyError(key)

            try:
                ordinal = tslib.iNaT if key is tslib.NaT else key.ordinal
                if tolerance is not None:
                    tolerance = self._convert_tolerance(tolerance)
                return self._int64index.get_loc(ordinal, method, tolerance)

            except KeyError:
                raise KeyError(key)
Exemple #3
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    def __setstate__(self, state):
        """Necessary for making this object picklable"""

        if isinstance(state, dict):
            super(PeriodIndex, self).__setstate__(state)

        elif isinstance(state, tuple):

            # < 0.15 compat
            if len(state) == 2:
                nd_state, own_state = state
                data = np.empty(nd_state[1], dtype=nd_state[2])
                np.ndarray.__setstate__(data, nd_state)

                # backcompat
                self.freq = Period._maybe_convert_freq(own_state[1])

            else:  # pragma: no cover
                data = np.empty(state)
                np.ndarray.__setstate__(self, state)

            self._data = data

        else:
            raise Exception("invalid pickle state")
Exemple #4
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    def asfreq(self, freq=None, how='E'):
        """
        Convert the PeriodIndex to the specified frequency `freq`.

        Parameters
        ----------

        freq : str
            a frequency
        how : str {'E', 'S'}
            'E', 'END', or 'FINISH' for end,
            'S', 'START', or 'BEGIN' for start.
            Whether the elements should be aligned to the end
            or start within pa period. January 31st ('END') vs.
            Janury 1st ('START') for example.

        Returns
        -------

        new : PeriodIndex with the new frequency

        Examples
        --------
        >>> pidx = pd.period_range('2010-01-01', '2015-01-01', freq='A')
        >>> pidx
        <class 'pandas.core.indexes.period.PeriodIndex'>
        [2010, ..., 2015]
        Length: 6, Freq: A-DEC

        >>> pidx.asfreq('M')
        <class 'pandas.core.indexes.period.PeriodIndex'>
        [2010-12, ..., 2015-12]
        Length: 6, Freq: M

        >>> pidx.asfreq('M', how='S')
        <class 'pandas.core.indexes.period.PeriodIndex'>
        [2010-01, ..., 2015-01]
        Length: 6, Freq: M
        """
        how = _validate_end_alias(how)

        freq = Period._maybe_convert_freq(freq)

        base1, mult1 = _gfc(self.freq)
        base2, mult2 = _gfc(freq)

        asi8 = self.asi8
        # mult1 can't be negative or 0
        end = how == 'E'
        if end:
            ordinal = asi8 + mult1 - 1
        else:
            ordinal = asi8

        new_data = period.period_asfreq_arr(ordinal, base1, base2, end)

        if self.hasnans:
            new_data[self._isnan] = tslib.iNaT

        return self._simple_new(new_data, self.name, freq=freq)
Exemple #5
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    def to_timestamp(self, freq=None, how='start'):
        """
        Cast to DatetimeIndex

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

        Returns
        -------
        DatetimeIndex
        """
        how = _validate_end_alias(how)

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

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

        new_data = period.periodarr_to_dt64arr(new_data._values, base)
        return DatetimeIndex(new_data, freq='infer', name=self.name)
Exemple #6
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def dt64arr_to_periodarr(data, freq, tz):
    if data.dtype != np.dtype('M8[ns]'):
        raise ValueError('Wrong dtype: %s' % data.dtype)

    freq = Period._maybe_convert_freq(freq)
    base, mult = _gfc(freq)
    return period.dt64arr_to_periodarr(data.view('i8'), base, tz)
Exemple #7
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def dt64arr_to_periodarr(data, freq, tz):
    if data.dtype != np.dtype('M8[ns]'):
        raise ValueError('Wrong dtype: %s' % data.dtype)

    freq = Period._maybe_convert_freq(freq)
    base, mult = _gfc(freq)
    return period.dt64arr_to_periodarr(data.view('i8'), base, tz)
Exemple #8
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    def asfreq(self, freq=None, how='E'):
        """
        Convert the PeriodIndex to the specified frequency `freq`.

        Parameters
        ----------

        freq : str
            a frequency
        how : str {'E', 'S'}
            'E', 'END', or 'FINISH' for end,
            'S', 'START', or 'BEGIN' for start.
            Whether the elements should be aligned to the end
            or start within pa period. January 31st ('END') vs.
            Janury 1st ('START') for example.

        Returns
        -------

        new : PeriodIndex with the new frequency

        Examples
        --------
        >>> pidx = pd.period_range('2010-01-01', '2015-01-01', freq='A')
        >>> pidx
        <class 'pandas.core.indexes.period.PeriodIndex'>
        [2010, ..., 2015]
        Length: 6, Freq: A-DEC

        >>> pidx.asfreq('M')
        <class 'pandas.core.indexes.period.PeriodIndex'>
        [2010-12, ..., 2015-12]
        Length: 6, Freq: M

        >>> pidx.asfreq('M', how='S')
        <class 'pandas.core.indexes.period.PeriodIndex'>
        [2010-01, ..., 2015-01]
        Length: 6, Freq: M
        """
        how = _validate_end_alias(how)

        freq = Period._maybe_convert_freq(freq)

        base1, mult1 = _gfc(self.freq)
        base2, mult2 = _gfc(freq)

        asi8 = self.asi8
        # mult1 can't be negative or 0
        end = how == 'E'
        if end:
            ordinal = asi8 + mult1 - 1
        else:
            ordinal = asi8

        new_data = period.period_asfreq_arr(ordinal, base1, base2, end)

        if self.hasnans:
            new_data[self._isnan] = tslib.iNaT

        return self._simple_new(new_data, self.name, freq=freq)
Exemple #9
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    def to_timestamp(self, freq=None, how='start'):
        """
        Cast to DatetimeIndex

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

        Returns
        -------
        DatetimeIndex
        """
        how = _validate_end_alias(how)

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

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

        new_data = period.periodarr_to_dt64arr(new_data._values, base)
        return DatetimeIndex(new_data, freq='infer', name=self.name)
Exemple #10
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    def wrapper(self, other):
        if isinstance(other, Period):
            func = getattr(self._values, opname)
            other_base, _ = _gfc(other.freq)
            if other.freq != self.freq:
                msg = _DIFFERENT_FREQ_INDEX.format(self.freqstr, other.freqstr)
                raise IncompatibleFrequency(msg)

            result = func(other.ordinal)
        elif isinstance(other, PeriodIndex):
            if other.freq != self.freq:
                msg = _DIFFERENT_FREQ_INDEX.format(self.freqstr, other.freqstr)
                raise IncompatibleFrequency(msg)

            result = getattr(self._values, opname)(other._values)

            mask = self._isnan | other._isnan
            if mask.any():
                result[mask] = nat_result

            return result
        elif other is tslib.NaT:
            result = np.empty(len(self._values), dtype=bool)
            result.fill(nat_result)
        else:
            other = Period(other, freq=self.freq)
            func = getattr(self._values, opname)
            result = func(other.ordinal)

        if self.hasnans:
            result[self._isnan] = nat_result

        return result
Exemple #11
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    def _maybe_cast_slice_bound(self, label, side, kind):
        """
        If label is a string or a datetime, cast it to Period.ordinal according
        to resolution.

        Parameters
        ----------
        label : object
        side : {'left', 'right'}
        kind : {'ix', 'loc', 'getitem'}

        Returns
        -------
        bound : Period or object

        Notes
        -----
        Value of `side` parameter should be validated in caller.

        """
        assert kind in ['ix', 'loc', 'getitem']

        if isinstance(label, datetime):
            return Period(label, freq=self.freq)
        elif isinstance(label, compat.string_types):
            try:
                _, parsed, reso = parse_time_string(label, self.freq)
                bounds = self._parsed_string_to_bounds(reso, parsed)
                return bounds[0 if side == 'left' else 1]
            except Exception:
                raise KeyError(label)
        elif is_integer(label) or is_float(label):
            self._invalid_indexer('slice', label)

        return label
Exemple #12
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    def __setstate__(self, state):
        """Necessary for making this object picklable"""

        if isinstance(state, dict):
            super(PeriodIndex, self).__setstate__(state)

        elif isinstance(state, tuple):

            # < 0.15 compat
            if len(state) == 2:
                nd_state, own_state = state
                data = np.empty(nd_state[1], dtype=nd_state[2])
                np.ndarray.__setstate__(data, nd_state)

                # backcompat
                self.freq = Period._maybe_convert_freq(own_state[1])

            else:  # pragma: no cover
                data = np.empty(state)
                np.ndarray.__setstate__(self, state)

            self._data = data

        else:
            raise Exception("invalid pickle state")
Exemple #13
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def pnow(freq=None):
    # deprecation, xref #13790
    import warnings

    warnings.warn("pd.pnow() and pandas.core.indexes.period.pnow() "
                  "are deprecated. Please use Period.now()",
                  FutureWarning, stacklevel=2)
    return Period.now(freq=freq)
Exemple #14
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def pnow(freq=None):
    # deprecation, xref #13790
    import warnings

    warnings.warn("pd.pnow() and pandas.core.indexes.period.pnow() "
                  "are deprecated. Please use Period.now()",
                  FutureWarning, stacklevel=2)
    return Period.now(freq=freq)
Exemple #15
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def _get_ordinal_range(start, end, periods, freq, mult=1):
    if com._count_not_none(start, end, periods) != 2:
        raise ValueError('Of the three parameters: start, end, and periods, '
                         'exactly two must be specified')

    if freq is not None:
        _, mult = _gfc(freq)

    if start is not None:
        start = Period(start, freq)
    if end is not None:
        end = Period(end, freq)

    is_start_per = isinstance(start, Period)
    is_end_per = isinstance(end, Period)

    if is_start_per and is_end_per and start.freq != end.freq:
        raise ValueError('start and end must have same freq')
    if (start is tslib.NaT or end is tslib.NaT):
        raise ValueError('start and end must not be NaT')

    if freq is None:
        if is_start_per:
            freq = start.freq
        elif is_end_per:
            freq = end.freq
        else:  # pragma: no cover
            raise ValueError('Could not infer freq from start/end')

    if periods is not None:
        periods = periods * mult
        if start is None:
            data = np.arange(end.ordinal - periods + mult,
                             end.ordinal + 1,
                             mult,
                             dtype=np.int64)
        else:
            data = np.arange(start.ordinal,
                             start.ordinal + periods,
                             mult,
                             dtype=np.int64)
    else:
        data = np.arange(start.ordinal, end.ordinal + 1, mult, dtype=np.int64)

    return data, freq
Exemple #16
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    def searchsorted(self, value, side='left', sorter=None):
        if isinstance(value, Period):
            if value.freq != self.freq:
                msg = _DIFFERENT_FREQ_INDEX.format(self.freqstr, value.freqstr)
                raise IncompatibleFrequency(msg)
            value = value.ordinal
        elif isinstance(value, compat.string_types):
            value = Period(value, freq=self.freq).ordinal

        return self._values.searchsorted(value, side=side, sorter=sorter)
Exemple #17
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    def get_value(self, series, key):
        """
        Fast lookup of value from 1-dimensional ndarray. Only use this if you
        know what you're doing
        """
        s = com._values_from_object(series)
        try:
            return com._maybe_box(self,
                                  super(PeriodIndex, self).get_value(s, key),
                                  series, key)
        except (KeyError, IndexError):
            try:
                asdt, parsed, reso = parse_time_string(key, self.freq)
                grp = resolution.Resolution.get_freq_group(reso)
                freqn = resolution.get_freq_group(self.freq)

                vals = self._values

                # if our data is higher resolution than requested key, slice
                if grp < freqn:
                    iv = Period(asdt, freq=(grp, 1))
                    ord1 = iv.asfreq(self.freq, how='S').ordinal
                    ord2 = iv.asfreq(self.freq, how='E').ordinal

                    if ord2 < vals[0] or ord1 > vals[-1]:
                        raise KeyError(key)

                    pos = np.searchsorted(self._values, [ord1, ord2])
                    key = slice(pos[0], pos[1] + 1)
                    return series[key]
                elif grp == freqn:
                    key = Period(asdt, freq=self.freq).ordinal
                    return com._maybe_box(self, self._engine.get_value(s, key),
                                          series, key)
                else:
                    raise KeyError(key)
            except TypeError:
                pass

            key = Period(key, self.freq).ordinal
            return com._maybe_box(self, self._engine.get_value(s, key), series,
                                  key)
Exemple #18
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    def get_value(self, series, key):
        """
        Fast lookup of value from 1-dimensional ndarray. Only use this if you
        know what you're doing
        """
        s = com._values_from_object(series)
        try:
            return com._maybe_box(self,
                                  super(PeriodIndex, self).get_value(s, key),
                                  series, key)
        except (KeyError, IndexError):
            try:
                asdt, parsed, reso = parse_time_string(key, self.freq)
                grp = frequencies.Resolution.get_freq_group(reso)
                freqn = frequencies.get_freq_group(self.freq)

                vals = self._values

                # if our data is higher resolution than requested key, slice
                if grp < freqn:
                    iv = Period(asdt, freq=(grp, 1))
                    ord1 = iv.asfreq(self.freq, how='S').ordinal
                    ord2 = iv.asfreq(self.freq, how='E').ordinal

                    if ord2 < vals[0] or ord1 > vals[-1]:
                        raise KeyError(key)

                    pos = np.searchsorted(self._values, [ord1, ord2])
                    key = slice(pos[0], pos[1] + 1)
                    return series[key]
                elif grp == freqn:
                    key = Period(asdt, freq=self.freq).ordinal
                    return com._maybe_box(self, self._engine.get_value(s, key),
                                          series, key)
                else:
                    raise KeyError(key)
            except TypeError:
                pass

            key = Period(key, self.freq).ordinal
            return com._maybe_box(self, self._engine.get_value(s, key),
                                  series, key)
Exemple #19
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    def _from_ordinals(cls, values, name=None, freq=None, **kwargs):
        """
        Values should be int ordinals
        `__new__` & `_simple_new` cooerce to ordinals and call this method
        """

        values = np.array(values, dtype='int64', copy=False)

        result = object.__new__(cls)
        result._data = values
        result.name = name
        if freq is None:
            raise ValueError('freq is not specified and cannot be inferred')
        result.freq = Period._maybe_convert_freq(freq)
        result._reset_identity()
        return result
Exemple #20
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    def _from_ordinals(cls, values, name=None, freq=None, **kwargs):
        """
        Values should be int ordinals
        `__new__` & `_simple_new` cooerce to ordinals and call this method
        """

        values = np.array(values, dtype='int64', copy=False)

        result = object.__new__(cls)
        result._data = values
        result.name = name
        if freq is None:
            raise ValueError('freq is not specified and cannot be inferred')
        result.freq = Period._maybe_convert_freq(freq)
        result._reset_identity()
        return result
Exemple #21
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    def _generate_range(cls, start, end, periods, freq, fields):
        if freq is not None:
            freq = Period._maybe_convert_freq(freq)

        field_count = len(fields)
        if com._count_not_none(start, end) > 0:
            if field_count > 0:
                raise ValueError('Can either instantiate from fields '
                                 'or endpoints, but not both')
            subarr, freq = _get_ordinal_range(start, end, periods, freq)
        elif field_count > 0:
            subarr, freq = _range_from_fields(freq=freq, **fields)
        else:
            raise ValueError('Not enough parameters to construct '
                             'Period range')

        return subarr, freq
Exemple #22
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    def _generate_range(cls, start, end, periods, freq, fields):
        if freq is not None:
            freq = Period._maybe_convert_freq(freq)

        field_count = len(fields)
        if com._count_not_none(start, end) > 0:
            if field_count > 0:
                raise ValueError('Can either instantiate from fields '
                                 'or endpoints, but not both')
            subarr, freq = _get_ordinal_range(start, end, periods, freq)
        elif field_count > 0:
            subarr, freq = _range_from_fields(freq=freq, **fields)
        else:
            raise ValueError('Not enough parameters to construct '
                             'Period range')

        return subarr, freq
Exemple #23
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 def _parsed_string_to_bounds(self, reso, parsed):
     if reso == 'year':
         t1 = Period(year=parsed.year, freq='A')
     elif reso == 'month':
         t1 = Period(year=parsed.year, month=parsed.month, freq='M')
     elif reso == 'quarter':
         q = (parsed.month - 1) // 3 + 1
         t1 = Period(year=parsed.year, quarter=q, freq='Q-DEC')
     elif reso == 'day':
         t1 = Period(year=parsed.year,
                     month=parsed.month,
                     day=parsed.day,
                     freq='D')
     elif reso == 'hour':
         t1 = Period(year=parsed.year,
                     month=parsed.month,
                     day=parsed.day,
                     hour=parsed.hour,
                     freq='H')
     elif reso == 'minute':
         t1 = Period(year=parsed.year,
                     month=parsed.month,
                     day=parsed.day,
                     hour=parsed.hour,
                     minute=parsed.minute,
                     freq='T')
     elif reso == 'second':
         t1 = Period(year=parsed.year,
                     month=parsed.month,
                     day=parsed.day,
                     hour=parsed.hour,
                     minute=parsed.minute,
                     second=parsed.second,
                     freq='S')
     else:
         raise KeyError(reso)
     return (t1.asfreq(self.freq,
                       how='start'), t1.asfreq(self.freq, how='end'))
Exemple #24
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    def __new__(cls, data=None, ordinal=None, freq=None, start=None, end=None,
                periods=None, copy=False, name=None, tz=None, dtype=None,
                **kwargs):

        if periods is not None:
            if is_float(periods):
                periods = int(periods)
            elif not is_integer(periods):
                raise ValueError('Periods must be a number, got %s' %
                                 str(periods))

        if name is None and hasattr(data, 'name'):
            name = data.name

        if dtype is not None:
            dtype = pandas_dtype(dtype)
            if not is_period_dtype(dtype):
                raise ValueError('dtype must be PeriodDtype')
            if freq is None:
                freq = dtype.freq
            elif freq != dtype.freq:
                msg = 'specified freq and dtype are different'
                raise IncompatibleFrequency(msg)

        # coerce freq to freq object, otherwise it can be coerced elementwise
        # which is slow
        if freq:
            freq = Period._maybe_convert_freq(freq)

        if data is None:
            if ordinal is not None:
                data = np.asarray(ordinal, dtype=np.int64)
            else:
                data, freq = cls._generate_range(start, end, periods,
                                                 freq, kwargs)
            return cls._from_ordinals(data, name=name, freq=freq)

        if isinstance(data, PeriodIndex):
            if freq is None or freq == data.freq:  # no freq change
                freq = data.freq
                data = data._values
            else:
                base1, _ = _gfc(data.freq)
                base2, _ = _gfc(freq)
                data = period.period_asfreq_arr(data._values,
                                                base1, base2, 1)
            return cls._simple_new(data, name=name, freq=freq)

        # not array / index
        if not isinstance(data, (np.ndarray, PeriodIndex,
                                 DatetimeIndex, Int64Index)):
            if is_scalar(data) or isinstance(data, Period):
                cls._scalar_data_error(data)

            # other iterable of some kind
            if not isinstance(data, (list, tuple)):
                data = list(data)

            data = np.asarray(data)

        # datetime other than period
        if is_datetime64_dtype(data.dtype):
            data = dt64arr_to_periodarr(data, freq, tz)
            return cls._from_ordinals(data, name=name, freq=freq)

        # check not floats
        if infer_dtype(data) == 'floating' and len(data) > 0:
            raise TypeError("PeriodIndex does not allow "
                            "floating point in construction")

        # anything else, likely an array of strings or periods
        data = _ensure_object(data)
        freq = freq or period.extract_freq(data)
        data = period.extract_ordinals(data, freq)
        return cls._from_ordinals(data, name=name, freq=freq)
Exemple #25
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 def _box_func(self):
     return lambda x: Period._from_ordinal(ordinal=x, freq=self.freq)
Exemple #26
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 def _box_func(self):
     return lambda x: Period._from_ordinal(ordinal=x, freq=self.freq)
Exemple #27
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    def __new__(cls,
                data=None,
                ordinal=None,
                freq=None,
                start=None,
                end=None,
                periods=None,
                copy=False,
                name=None,
                tz=None,
                dtype=None,
                **kwargs):

        if periods is not None:
            if is_float(periods):
                periods = int(periods)
            elif not is_integer(periods):
                msg = 'periods must be a number, got {periods}'
                raise TypeError(msg.format(periods=periods))

        if name is None and hasattr(data, 'name'):
            name = data.name

        if dtype is not None:
            dtype = pandas_dtype(dtype)
            if not is_period_dtype(dtype):
                raise ValueError('dtype must be PeriodDtype')
            if freq is None:
                freq = dtype.freq
            elif freq != dtype.freq:
                msg = 'specified freq and dtype are different'
                raise IncompatibleFrequency(msg)

        # coerce freq to freq object, otherwise it can be coerced elementwise
        # which is slow
        if freq:
            freq = Period._maybe_convert_freq(freq)

        if data is None:
            if ordinal is not None:
                data = np.asarray(ordinal, dtype=np.int64)
            else:
                data, freq = cls._generate_range(start, end, periods, freq,
                                                 kwargs)
            return cls._from_ordinals(data, name=name, freq=freq)

        if isinstance(data, PeriodIndex):
            if freq is None or freq == data.freq:  # no freq change
                freq = data.freq
                data = data._values
            else:
                base1, _ = _gfc(data.freq)
                base2, _ = _gfc(freq)
                data = period.period_asfreq_arr(data._values, base1, base2, 1)
            return cls._simple_new(data, name=name, freq=freq)

        # not array / index
        if not isinstance(
                data, (np.ndarray, PeriodIndex, DatetimeIndex, Int64Index)):
            if is_scalar(data) or isinstance(data, Period):
                cls._scalar_data_error(data)

            # other iterable of some kind
            if not isinstance(data, (list, tuple)):
                data = list(data)

            data = np.asarray(data)

        # datetime other than period
        if is_datetime64_dtype(data.dtype):
            data = dt64arr_to_periodarr(data, freq, tz)
            return cls._from_ordinals(data, name=name, freq=freq)

        # check not floats
        if infer_dtype(data) == 'floating' and len(data) > 0:
            raise TypeError("PeriodIndex does not allow "
                            "floating point in construction")

        # anything else, likely an array of strings or periods
        data = _ensure_object(data)
        freq = freq or period.extract_freq(data)
        data = period.extract_ordinals(data, freq)
        return cls._from_ordinals(data, name=name, freq=freq)