These are the changes in pandas 1.6.0. See :ref:`release` for a full changelog including other versions of pandas.
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- :meth:`Series.add_suffix`, :meth:`DataFrame.add_suffix`, :meth:`Series.add_prefix` and :meth:`DataFrame.add_prefix` support an
axisargument. Ifaxisis set, the default behaviour of which axis to consider can be overwritten (:issue:`47819`)
These are bug fixes that might have notable behavior changes.
Using :meth:`DataFrame.at` raises when trying to add a new column with multiple values
Old behavior
In [1]: import pandas as pd
In [2]: df = pd.DataFrame({"a": [1, 2, 3], "b": [4, 5, 6]})
In [3]: # should raise InvalidIndexError
df.at[slice(0, 1, None), 'c'] = 7
In [4]: df
Out[4]:
a b c
0 1 4 7.0
1 2 5 7.0
2 3 6 NaN
New behavior
In [1]: import pandas as pd
In [2]: df = pd.DataFrame({"a": [1, 2, 3], "b": [4, 5, 6]})
In [3]: df.at[slice(0, 1, None), 'c'] = 7
---------------------------------------------------------------------------
InvalidIndexError Traceback (most recent call last)
<ipython-input-3-a89a95224c2b> in <module>
----> 1 df.at[slice(0, 1, None), 'c'] = 7
Some minimum supported versions of dependencies were updated. If installed, we now require:
| Package | Minimum Version | Required | Changed |
|---|---|---|---|
| X | X |
For optional libraries the general recommendation is to use the latest version. The following table lists the lowest version per library that is currently being tested throughout the development of pandas. Optional libraries below the lowest tested version may still work, but are not considered supported.
| Package | Minimum Version | Changed |
|---|---|---|
| X |
See :ref:`install.dependencies` and :ref:`install.optional_dependencies` for more.
- Performance improvement for :meth:`MultiIndex.unique` (:issue:`48335`)
- Bug in :meth:`DataFrame.reindex` filling with wrong values when indexing columns and index for
uintdtypes (:issue:`48184`)
- Bug in :meth:`MultiIndex.unique` losing extension array dtype (:issue:`48335`)
- Bug in :meth:`MultiIndex.append` not checking names for equality (:issue:`48288`)