Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 823 22.11.6 Side Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 824 note in each release. v0.19.1 (November 3, 2016) This is a minor bug-fix release from 0.19.0 and includes some small regression fixes, bug fixes and performance improvements. We recommend that all users values is not specified (GH14380) v0.19.0 (October 2, 2016) This is a major release from 0.18.1 and includes number of API changes, several new features, enhancements, and performance improvements along with

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 821 22.11.6 Side Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 822 improvements of note in each release. v0.19.0 (October 2, 2016) This is a major release from 0.18.1 and includes number of API changes, several new features, enhancements, and performance improvements along with border option, which defaults to 1. This also affects the notebook HTML repr, but since Jupyter’s CSS includes a border-width attribute, the visual effect is the same. (GH11563). • Raise ImportError in the

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 910 21.11.6 Side Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 911 each release. 1.1 v0.20.3 (July 7, 2017) This is a minor bug-fix release in the 0.20.x series and includes some small regression fixes and bug fixes. We recommend that all users upgrade to this version. (GH16793) 1.2 v0.20.2 (June 4, 2017) This is a minor bug-fix release in the 0.20.x series and includes some small regression fixes, bug fixes and performance improvements. We recommend that all users

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 944 21.12.5 Side Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 944 release. 1.1 v0.21.1 (December 12, 2017) This is a minor bug-fix release in the 0.21.x series and includes some small regression fixes, bug fixes and performance improvements. We recommend that all users datetime or Period values. Prior to pandas 0.21.0, these were implicitly registered with matplotlib, as a side effect of import pandas. In pandas 0.21.0, we required users to explicitly register the converter

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 906 21.11.6 Side Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 907 each release. 1.1 v0.20.2 (June 4, 2017) This is a minor bug-fix release in the 0.20.x series and includes some small regression fixes, bug fixes and performance improvements. We recommend that all users non-unique indices (GH16270) 1.2 v0.20.1 (May 5, 2017) This is a major release from 0.19.2 and includes a number of API changes, deprecations, new features, enhancements, and performance improvements

exponential (or Poisson) window type (GH21303) • Error message for missing required imports now includes the original import error’s text (GH23868) • DatetimeIndex and TimedeltaIndex now have a mean method on the first group to infer if it is safe to use a fast code path. Particularly for functions with side effects, this was an undesired behavior and may have led to surprises. (GH2936, GH2656, GH7739, GH10519 division and modulo operation at the same time returning a two-tuple of the same type as the left hand side. For example: In [29]: s = pd.Series(np.arange(10)) In [30]: s Out[30]: 0 0 1 1 2 2 3 3 4 4

exponential (or Poisson) window type (GH21303) • Error message for missing required imports now includes the original import error’s text (GH23868) • DatetimeIndex and TimedeltaIndex now have a mean method on the first group to infer if it is safe to use a fast code path. Particularly for functions with side effects, this was an undesired behavior and may have led to surprises. (GH2936, GH2656, GH7739, GH10519 division and modulo operation at the same time returning a two-tuple of the same type as the left hand side. For example: In [29]: s = pd.Series(np.arange(10)) In [30]: s Out[30]: 0 0 1 1 2 2 3 3 4 4

Python 3 only. See Plan for dropping Python 2.7 for more. This is a major release from 0.23.4 and includes a number of API changes, new features, enhancements, and perfor- mance improvements along with a support tilde(~) in path argument. (GH23473) 1.2 Backwards incompatible API changes Pandas 0.24.0 includes a number of API breaking changes. 1.2.1 Increased minimum versions for dependencies We have updated division and modulo operation at the same time returning a two-tuple of the same type as the left hand side. For example: In [33]: s = pd.Series(np.arange(10)) In [34]: s Out[34]: 0 0 1 1 2 2 3 3 4 4

NaN 61.9 NaN NaN To create a new column, use the [] brackets with the new column name at the left side of the assignment. 1.4. Tutorials 35 pandas: powerful Python data analysis toolkit, Release 1.5 Pclass, dtype: int64 Note: Both size and count can be used in combination with groupby. Whereas size includes NaN values and just provides the number of rows (size of the table), count excludes the missing • Ease-of-use: Is one tool easier/harder to use (you may have to be the judge of this, given side-by-side code comparisons) This page is also here to offer a bit of a translation guide for users of these

of note in each release. 1.1 v0.17.0 (October 9, 2015) This is a major release from 0.16.2 and includes a small number of API changes, several new features, enhancements, and performance improvements scatter df.plot.bar df.plot.box df.plot.hexbin df.plot.kde df.plot.pie Each method signature only includes relevant arguments. Currently, these are limited to required arguments, but in the future these numeric reduction operators would return ValueError, rather than TypeError on object types that includes strings and numbers (GH11131) • Passing currently unsupported chunksize argument to read_excel