tables and cross-tabulations ..... 161 13 Time Series / Date functionality ..... 165 13.1 DateOffset objects ..... 165 13.2 Generating date ranges (DateRange) ..... 167 13.3 Time series-related ‘^’, ‘-’ on DataFrame (GH347) • Added Series.mad, mean absolute deviation • Added QuarterEnd DateOffset (PR321) • Added dot to DataFrame (GH65) • Added orient option to Panel.from_dict (GH359, GH301) hierarchical index object • DateRange: fixed frequency date range generated from a time rule or DateOffset. An ndarray of Python datetime objects The motivation for having an Index class in the first place

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418 16.5 DateOffset objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 days, 00:00:00 1 62 days, 00:00:00 2 93 days, 00:15:09 3 NaT dtype: timedelta64[ns] Absolute DateOffset objects can act equivalently to timedeltas In [80]: from pandas import offsets In [81]: td + offsets ‘|’, ‘^’, ‘-‘ on DataFrame (GH347) • Added Series.mad, mean absolute deviation • Added QuarterEnd DateOffset (GH321) • Added dot to DataFrame (GH65) • Added orient option to Panel.from_dict (GH359, GH301)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 506 19.5 DateOffset objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (GH7914) • Bug in Timestamp comparisons with == and int64 dtype (GH8058) • Bug in pickles contains DateOffset may raise AttributeError when normalize attribute is reffered internally (GH7748) • Bug in Panel • Bug in DataFrame.to_latex formatting when columns or index is a MultiIndex (GH7982). • Bug in DateOffset around Daylight Savings Time produces unexpected results (GH5175). • Bug in DataFrame.shift where

... 493 19.3 Generating Ranges of Timestamps ..... 494 19.4 DatetimeIndex ..... 496 19.5 DateOffset objects ..... 502 19.6 Time series-related instance methods ..... 511 19.7 Up- and downsampling (GH7914) • Bug in Timestamp comparisons with == and int64 dtype (GH8058) • Bug in pickles contains DateOffset may raise AttributeError when normalize attribute is referred internally (GH7748) • Bug in Panel Bug in DataFrame.to_latex formatting when columns or index is a MultiIndex (GH7982). • Bug in DateOffset around Daylight Savings Time produces unexpected results (GH5175). • Bug in DataFrame.shift where

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 596 20.6 DateOffset objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . period_range can now accept multiplied freq. Also, Period.freq and PeriodIndex.freq are now stored as a DateOffset instance like DatetimeIndex, and not as str (GH7811) A multiplied freq represents a span of corresponding Timestamp.now() Out[67]: Timestamp('2015-10-09 20:59:45.917782') In [68]: Timestamp.now() + offsets.DateOffset(years=1) Out[68]: Timestamp('2016-10-09 20:59:45.919984') Changes to Index Comparisons Operator

future version (GH29812) • DateOffset.isAnchored() and DatetOffset.onOffset() are deprecated and will be removed in a future version, use DateOffset.is_anchored() and DateOffset.is_on_offset() instead (GH30340) a Timestamp or Timedelta (GH30175) • Bug in DatetimeIndex addition when adding a non-optimized DateOffset incorrectly dropping timezone information (GH30336) • Bug in DataFrame.drop() where attempting Time spans Period PeriodIndex period[freq] Period or period_range Date offsets DateOffsetNone None DateOffset For time series data, it’s conventional to represent the time component in the index of a Series

components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 741 2.14.8 DateOffset objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 742 2.14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1953 3.8.1 DateOffset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1953 3 Time spans Period PeriodIndex period[freq] Period or period_range Date offsets DateOffsetNone None DateOffset For time series data, it’s conventional to represent the time component in the index of a Series

components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 739 3.14.8 DateOffset objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 740 3.14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1951 4.8.1 DateOffset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1951 4 Time spans Period PeriodIndex period[freq] Period or period_range Date offsets DateOffsetNone None DateOffset For time series data, it’s conventional to represent the time component in the index of a Series

components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 856 2.20.8 DateOffset objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 857 2.20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2232 3.7.1 DateOffset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2232 vii timedelta_range Time spans Period PeriodIndex period[freq] Period or period_range Date off- sets DateOffset None None DateOffset For time series data, it’s conventional to represent the time component in the index

components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 855 2.20.8 DateOffset objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 856 2.20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2232 3.7.1 DateOffset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2232 vii timedelta_range Time spans Period PeriodIndex period[freq] Period or period_range Date off- sets DateOffset None None DateOffset For time series data, it’s conventional to represent the time component in the index