Hi, is there anything like pandas groupby (split-apply-combine) http://pandas.pydata.org/pandas-docs/stable/groupby.html.
I would like to spilt a big DataFrame into many small DataFrames according some columns.
On each group, I would like to apply a predefine function which will return another data object.
Finally, return a map of <key, result data object. Or if each group returns a DataFrame, I would like to combine them into a big DataFrame.
In short words, something like:
DataFrame.groupby(columns...).foreach(rows => ...)
DataFrame.groupby(columns...).foreach(rows => ...).collect(...)