[ARROW-7914] [Python] Allow pandas datetime as index for feather

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 0.15.1
• Fix Version/s: 8.0.0
• Component/s: Python
• Labels: arrow datetime feather pull-request-available python
• Environment: Windows, python 3.6.7,
• External issue URL: https://github.com/apache/arrow/issues/24135
• Assignee: saloni jain
• Reporter: Samuel Jones
• Created: 21/Feb/20 18:00
• Updated: 11/Jan/23 07:56
• Resolved: 21/Apr/22 16:48

Description

Sorry in advance if I mess anything up. This is my first issue.

I have hourly data for 3 years using a  Pandas datetime as the index. Pandas allows me load/save .csv with the following code (only one month with 2 variables shown):
`

Write data to .csv

jan90.to_csv('PEC fine course 1 grid 199001.csv', index=True)

Load data from .csv

jan90 = pd.read_csv('PEC fine course 1 grid 199001.csv', index_col=0, parse_dates=True)
`
Using .csv works, but is slow when I get to the full dataset of 26k+ rows and 21.6k+ columns (and more columns may be coming if I have to add lags to my data). So, a more efficient load/save routine is very desirable. I was excited when I found feather, but the lost index is a no-go for my use.

Thanks for your consideration.

Issue Links

• duplicates: ARROW-15018 [Python] DataFrame Index modified during Feather serialization round trip
• links to: GitHub Pull Request #12821