Best way to read a csv (* without a header *) sort and store back to disk

Question

I have a csv file with four columns (no header). I would like to sort the file by the first, then second column, and store back to disk.

I can read the file in using pandas or numpy, no problem, but not sure how to sort it, and store.

@leoschet yes, probably, but I want to know how to do this programmatically — Jacko, Jun 18 '18 at 22:06
Possible duplicate of [How to sort a dataFrame in python pandas by two or more columns?](https://stackoverflow.com/questions/17141558/how-to-sort-a-dataframe-in-python-pandas-by-two-or-more-columns) — Evgeny, Jun 18 '18 at 22:11
what've you tried? quick search gives me: [pandas doc](http://pandas.pydata.org/pandas-docs/version/0.19/generated/pandas.DataFrame.sort.html) and [stackoverflow](https://stackoverflow.com/questions/37787698/how-to-sort-pandas-dataframe-from-one-column) — leoschet, Jun 18 '18 at 22:13

MaxU - stand with Ukraine · Accepted Answer · 2018-06-19T10:08:47.193

5

just like you wanted to process:

If we chain all steps together, then we don't even need to create a variable for the DataFrame...

Demo:

(pd.read_csv('/path/to/file.csv', header=None)
   .sort_values([0,1])
   .to_csv('/path/to/result.csv', index=False, header=None))

edited Jun 19 '18 at 10:08

answered Jun 18 '18 at 22:09

1

@kmario23, it's a fair point. I've added a short explanation... – MaxU - stand with Ukraine Jun 19 '18 at 10:09

1 Answers1