We rapidly improved and added new functionalities, especially for groupby-related functionalities, in the past weeks. We also added the following features:
koalas.groupby.GroupBy:
size() (#593)
filter() (#614)
cummax() (#610)
cummin() (#610)
cumsum() (#610)
cumprod() (#610)
rand() (#619)
koalas.groupby.SeriesGroupBy:
apply() (#609)
value_counts() (#613)
koalas.indexes.Index:
size() (#623)
Along with the following improvements:
Add multiple aggregations on a single column (#602)
Add axis=columns to count, var, std, max, sum, min, kurtosis, skew and mean in DataFrame (#605)
Add Spark DDL formatted string support in read_csv(names=…) (#604)
Support names of index levels (#621, #629)
Add as_index argument to groupby. (#627)
Fix issues related to multi-index column access (#594, #597, #606, #611, #612, #620)