Reputation: 932
I have an 'hour' column in a pandas dataframe that is simply a list of numbers from 0 to 23 representing hours. How can I convert them to an hour format such as 01:00 when the numbers are single digit ( like 1 ) and double digit (like 18)? The single digit numbers need to have a leading zero, a colon and two trailing zeros. The double digit numbers need only a colon and two trailing zeros. How can this be accomplished in a dataframe? Also, I have a 'date' column that needs to merge with the hour column after the hour column is converted.
e.g. date hour
2018-07-01 0
2018-07-01 1
2018-07-01 3
...
2018-07-01 21
2018-07-01 22
2018-07-01 23
Needs to look like:
date
2018-07-01 01:00
...
2018-07-01 23:00
The source of the data is a .csv file. Thanks for your consideration. I'm new to pandas and I can't find in their documentation how to do this considering the single and double digit numbers.
Upvotes: 2
Views: 339
Reputation: 862791
Convert hours to timedeltas by to_timedelta
and add to datetimes converted by to_datetime
if necessary:
df['date'] = pd.to_datetime(df['date']) + pd.to_timedelta(df['hour'], unit='h')
print (df)
date hour
0 2018-07-01 00:00:00 0
1 2018-07-01 01:00:00 1
2 2018-07-01 03:00:00 3
3 2018-07-01 21:00:00 21
4 2018-07-01 22:00:00 22
5 2018-07-01 23:00:00 23
If need also remove hour
column use DataFrame.pop
df['date'] = pd.to_datetime(df['date']) + pd.to_timedelta(df.pop('hour'), unit='h')
print (df)
date
0 2018-07-01 00:00:00
1 2018-07-01 01:00:00
2 2018-07-01 03:00:00
3 2018-07-01 21:00:00
4 2018-07-01 22:00:00
5 2018-07-01 23:00:00
Upvotes: 2