GH4375, GH4372) • deprecated the string method match, whose role is now performed more idiomatically by extract. In a future release, the default behavior of match will change to become analogous to contains contains, which returns a boolean indexer. (Their distinction is strictness: match relies on re.match while contains relies on re.search.) In this release, the deprecated behavior is the default, but the new 5.0 4 dtype: int64 Scalar selection for [],.ix,.loc will always be label based. An integer will match an equal float index (e.g. 3 is equivalent to 3.0) In [29]: s[3] Out[29]: 2 In [30]: s.ix[3] Out[30]:

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 591 10.3.1 Extract first match in each subject (extract) . . . . . . . . . . . . . . . . . . . . . . . . . . 591 10.3.2 Extract (extractall) . . . . . . . . . . . . . . . . . . . . . . . . . 592 10.4 Testing for Strings that Match or Contain a Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . 594 10.5 Creating Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 851 19.6.2 Slice vs. Exact Match . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 856 19.6.3 Exact Indexing

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 563 10.3.1 Extract first match in each subject (extract) . . . . . . . . . . . . . . . . . . . . . . . . . . 563 10.3.2 Extract (extractall) . . . . . . . . . . . . . . . . . . . . . . . . . 565 10.4 Testing for Strings that Match or Contain a Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . 566 10.5 Creating Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 820 19.6.2 Slice vs. exact match . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 825 19.6.3 Exact Indexing

Index([1, 2, 3]) == pd.Index([2]) ValueError: Lengths must match to compare In [10]: pd.Index([1, 2, 3]) == pd.Index([1, 2]) ValueError: Lengths must match to compare Note that this is different from the numpy analysis toolkit, Release 0.17.0 • Bug in which groupby.transform incorrectly enforced output dtypes to match input dtypes. (GH9807) • Bug in DataFrame constructor when columns parameter is set, and data is defines .seconds as 10 * 3600 + 11 * 60 + 12 == 36672. So in v0.16.0, we are restoring the API to match that of datetime.timedelta. Further, the component values are still available through the .components

no experimental changes in 0.14.0 1.1.14 Bug Fixes • Bug in Series ValueError when index doesn’t match data (GH6532) • Prevent segfault due to MultiIndex not being supported in HDFStore table format (GH1848) replace() when passing a nested dict that contained keys not in the values to be replaced (GH6342) • str.match ignored the na flag (GH6609). • Bug in take with duplicate columns that were not consolidated (GH6240) affecting NaT (GH6873) • Bug in Series.str.extract where the resulting Series from a single group match wasn’t renamed to the group name • Bug in DataFrame.to_csv where setting index=False ignored the

arithmetic operations (+, -, ...). The behavior of the comparison operations has been changed to match the arithmetic operations in these cases. (GH22880) The affected cases are: • operating against (GH20591) • The column order of the resultant DataFrame from MultiIndex.to_frame() is now guaranteed to match the MultiIndex.names order. (GH22420) • Incorrectly passing a DatetimeIndex to MultiIndex.from_tuples() __hash__. If you have a parametrized dtype, you should update the ExtensionDtype. _metadata tuple to match the signature of your __init__ method. See pandas.api.extensions. ExtensionDtype for more (GH22476)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 561 10.3.1 Extract first match in each subject (extract) . . . . . . . . . . . . . . . . . . . . . . . . . . 561 10.3.2 Extract (extractall) . . . . . . . . . . . . . . . . . . . . . . . . . 563 10.4 Testing for Strings that Match or Contain a Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . 564 10.5 Creating Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 816 19.6.2 Slice vs. exact match . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 821 19.6.3 Exact Indexing

previous behavior of returning locations for overlapping matches. A KeyError will be raised if an exact match is not found. Previous behavior: In [6]: ii.get_loc(pd.Interval(1, 5)) Out[6]: array([0, 1]) In also only return locations for exact matches to Interval queries, with -1 denoting that an exact match was not found. These indexing changes extend to querying a Series or DataFrame with an IntervalIndex ignored (GH16807) • Bug in SparseDataFrame when adding a column in which the length of values does not match length of index, AssertionError is raised instead of raising ValueError (GH25484) • Introduce a better

previous behavior of returning locations for overlapping matches. A KeyError will be raised if an exact match is not found. Previous behavior: In [6]: ii.get_loc(pd.Interval(1, 5)) Out[6]: array([0, 1]) In also only return locations for exact matches to Interval queries, with -1 denoting that an exact match was not found. These indexing changes extend to querying a Series or DataFrame with an IntervalIndex ignored (GH16807) • Bug in SparseDataFrame when adding a column in which the length of values does not match length of index, AssertionError is raised instead of raising ValueError (GH25484) • Introduce a better

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 501 11.3.1 Extract first match in each subject (extract) . . . . . . . . . . . . . . . . . . . . . . . . . . 501 11.3.2 Extract (extractall) . . . . . . . . . . . . . . . . . . . . . . . . . 503 11.4 Testing for Strings that Match or Contain a Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . 505 11.5 Creating Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1054 32.2.3 match / %in% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1055 32