Adding a timestamp to a pandas dataframe

Question

I am doing some web scraping and storing the results in a Pandas Dataframe to subsequently output to csv. My questions is: how can I add a timestamp to the top of the Dataframe to record when I did the web scraping?

For example:

df1 = pd.DataFrame({'Fruits':['Apple','Banana','Cherry']})

would print:

  Fruits
0  Apple
1 Banana
2 Cherry

how can I print:

9/9/2017
  Fruits
0  Apple
1 Banana
2 Cherry

possible duplicate of https://stackoverflow.com/questions/14688306/adding-meta-information-metadata-to-pandas-dataframe — Dave Kielpinski, Sep 08 '17 at 20:28

cs95 · Accepted Answer · 2017-09-09T22:57:21.607

0

Option 1

Setting df.index.name

df1.index.name = pd.Timestamp('9/9/2017')
df1

                     Fruits
2017-09-09 00:00:00        
0                     Apple
1                    Banana
2                    Cherry

Option 2

Using df.rename_axis:

df1 = df1.rename_axis(pd.Timestamp('9/9/2017'))
df1

                     Fruits
2017-09-09 00:00:00        
0                     Apple
1                    Banana
2                    Cherry

edited Sep 09 '17 at 22:57

answered Sep 08 '17 at 23:19

cs95

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Yes, it works for me. However, when I convert df1 to csv using df1.to_csv, the timestamp doesn't print out. Any idea why? – Eric Choi Sep 09 '17 at 05:07
@EricChoi You could instead do `df1.index.name = pd.Timestamp('9/9/2017')`. That retains it. I'm not sure why the former doesn't work. – cs95 Sep 09 '17 at 05:14
@COLDSPEED Works very well now. Thank you very much. – Eric Choi Sep 09 '17 at 07:58

Adding a timestamp to a pandas dataframe

1 Answers1