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Wes McKinney commented on ARROW-376: ------------------------------------ [~ahnj] if you don't mind, I will take care of this one. It requires a bit of work to expose the {{custom_metadata}} fields in the file metadata > Python: Convert non-range Pandas indices (optionally) to Arrow > -------------------------------------------------------------- > > Key: ARROW-376 > URL: https://issues.apache.org/jira/browse/ARROW-376 > Project: Apache Arrow > Issue Type: Improvement > Components: Python > Reporter: Uwe L. Korn > Assignee: Wes McKinney > Priority: Minor > Labels: newbie > Fix For: 0.3.0 > > > Currently the indices of a Pandas DataFrame are totally ignored on the Pandas > to Arrow conversion. We should add an option to also convert the index to an > Arrow column if they are not a simple range index. > The condition for a simple index should be {{isinstance(df.index, > pd.RangeIndex) && (df.index._start == 0) && (df.index._stop == len(df.index)) > && (df.index._step == 1)}}. In this case, we can always skip the index > conversion. Otherwise, a new column in the Arrow table shall be created using > the index' name as the name of the column. Additionally there should be some > metadata annotation of that column that it is derived of an Pandas Index, so > that for roundtrips, we'll use it again as the index of a DataFrame. -- This message was sent by Atlassian JIRA (v6.3.15#6346)