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pd.to_datetime Hours and Seconds

Good Evening,

I have a dataframe(Pandas), with a column representing dates, in the following format:

print(df["date"])

14/01/18 12:47
14/01/18 12:48
14/01/18 12:50
14/01/18 12:57
14/01/18 12:57
14/01/18 12:57
14/01/18 12:57
14/01/18 12:57
14/01/18 12:58

Specifically, I would like to: 1. Convert it to datetime, using pd.to_datetime 2. Create the following additional columns:

df["month"]
df["day"]
df["year"]
df["hour"]
df["minute"]

I tried to run:

df['date'] = pd.to_datetime(df['date'], format = "%d/%m/%Y %H/%M" )

But the following error appears:

time data '02/01/18 08:41' does not match format '%d/%m/%Y %H/%M' (match)
like image 202
Alessandro Ceccarelli Avatar asked Jan 25 '18 13:01

Alessandro Ceccarelli


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2 Answers

The format you want is '%d/%m/%y %H:%M' (lowercase y and colon between hour and minute). Take a look here.

Then you can create the other columns:

df['month'] = df['date'].apply(lambda x: x.month)
df['day'] = df['date'].apply(lambda x: x.day)
df['year'] = df['date'].apply(lambda x: x.year)
df['hour'] = df['date'].apply(lambda x: x.hour)
df['minute'] = df['date'].apply(lambda x: x.minute)
like image 124
grovina Avatar answered Oct 08 '22 05:10

grovina


Alternatively to grovina's answer ... instead of using apply you can directly use the dt accessor.

Here's a sample:

>>> data = [['2017-12-01'], ['2017-12-30'],['2018-01-01']]
>>> df = pd.DataFrame(data=data, columns=['date'])
>>> df
         date
0  2017-12-01
1  2017-12-30
2  2018-01-01
>>> df.date
0    2017-12-01
1    2017-12-30
2    2018-01-01
Name: date, dtype: object

Note how df.date is an object? Let's turn it into a date like you want

>>> df.date = pd.to_datetime(df.date)
>>> df.date
0   2017-12-01
1   2017-12-30
2   2018-01-01
Name: date, dtype: datetime64[ns]

The format you want is for string formatting. I don't think you'll be able to convert the actual datetime64 to look like that format. For now, let's make a newly formatted string version of your date in a separate column

 >>> df['new_formatted_date'] = df.date.dt.strftime('%d/%m/%y %H:%M')
 >>> df.new_formatted_date
 0    01/12/17 00:00
 1    30/12/17 00:00
 2    01/01/18 00:00
 Name: new_formatted_date, dtype: object

Finally, since the df.date column is now of date datetime64... you can use the dt accessor right on it. No need to use apply

>>> df['month'] = df.date.dt.month
>>> df['day'] = df.date.dt.day
>>> df['year'] = df.date.dt.year
>>> df['hour'] = df.date.dt.hour
>>> df['minute'] = df.date.dt.minute
>>> df
        date new_formatted_date  month  day  year  hour  minute
0 2017-12-01     01/12/17 00:00     12    1  2017     0       0
1 2017-12-30     30/12/17 00:00     12   30  2017     0       0
2 2018-01-01     01/01/18 00:00      1    1  2018     0       0
like image 21
Orenshi Avatar answered Oct 08 '22 04:10

Orenshi