如何阻止 Pandas 从 csv 文件中删除封闭字符？

Question

I had to trim a very large csv file and I decided to use pandas for it. The file is a CSV and every value in the CSV is enclosed by double quotes. So the file looked like

"Col1", "Col2", "Col3"
"foo", "fii", "fuu"

However, upon using df = pd.read_csv(path, encoding='Latin1', low_memory=False) all of the double quotes get removed, and after trimming the file and exporting it with df.to_csv to a new csv, the new csv has

col1, col2, col3
foo, fii, fuu

With no enclosing characters. I definitely need those double quotes, is there a way to preserve them or to add them again?

Answer 1

solution

https://docs.python.org/3/library/csv.html#csv.QUOTE_ALL

import csv
df.to_csv('out.csv',header=True, quoting=csv.QUOTE_ALL)

Answer 2

It looks like you can read csv with quotechar option set to something else:

from io import StringIO

s = '''"Col1", "Col2", "Col3"
"foo", "fii", "fuu"'''

pd.read_csv(StringIO(s), quotechar="'")

Output:

  "Col1"  "Col2"  "Col3"
0  "foo"   "fii"   "fuu"