Version 0.19.0

Koalas Logo

Now that we have an official logo!

We can see the cute logo in our documents as well.

Documentation

Also we improved the documentation: https://koalas.readthedocs.io/en/latest/

• Added the logo (#831)
• Added a Jupyter notebook for 10 min tutorial (#843)
• Added the tutorial to the documentation (#853)
• Add some examples for plot implementations in their docstrings (#847)
• Move contribution guide to the official documentation site (#841)

Binder integration for the 10 min tutorial

You can run a live Jupyter notebook for 10 min tutorial from .

Multi-index columns support

We continue improving multi-index columns support. We made the following APIs support multi-index columns:

• transform (#800)
• round (#802)
• unique (#809)
• duplicated (#803)
• assign (#811)
• merge (#825)
• plot (#830)
• groupby and its functions (#833)
• update (#848)
• join (#848)
• drop_duplicate (#856)
• dtype (#858)
• filter (#859)
• dropna (#857)
• replace (#860)

Plots

We also continue adding plot APIs as follows:

For DataFrame:

• plot.kde() (#784)

Other new features and improvements

We added the following new features:

koalas.DataFrame:

• pop (#791)
• __iter__ (#836)
• rename (#806)
• expanding (#840)
• rolling (#840)

koalas.Series:

• aggregate (#816)
• agg (#816)
• expanding (#840)
• rolling (#840)
• drop (#829)
• copy (#869)

koalas.DataFrameGroupBy:

• expanding (#840)
• rolling (#840)

koalas.SeriesGroupBy:

• expanding (#840)
• rolling (#840)

Along with the following improvements:

• Add squeeze argument to read_csv (#812)
• Raise a more helpful error for duplicated columns in Join (#820)
• Issue with ks.merge to Series (#818)
• Fix MultiIndex.to_pandas() and __repr__(). (#832)
• Add unit and origin options for to_datetime (#839)
• Fix on wrong error raise in DataFrame.fillna (#844)
• Allow str and list in aggfunc in DataFrameGroupby.agg (#828)
• Add index_col argument to to_koalas(). (#863)