python - Multiple columns extracted from one Pandas column -


i have (parsed) datetime column in pandas dataframe. need generate multiple columns based on 1 column, 1 year, 1 month, hour, day of week etcetera. i'm doing number of individual applies large dataset , i'm iterating on df multiple times. there better pattern accomplish this? can apply return dataframe paste behind it?

if dtype datetime can use vectorised datetime accessor dt add columns:

in [11]: df = pd.dataframe({'date':pd.date_range(dt.datetime(2016,1,1), end = dt.datetime(2016,1,10))}) df  out[11]:         date 0 2016-01-01 1 2016-01-02 2 2016-01-03 3 2016-01-04 4 2016-01-05 5 2016-01-06 6 2016-01-07 7 2016-01-08 8 2016-01-09 9 2016-01-10  in [13]:     df['year'],df['month'],df['day'], df['day_of_week'] = df['date'].dt.year, df['date'].dt.month, df['date'].dt.day, df['date'].dt.dayofweek df  out[13]:         date  year  month  day  day_of_week 0 2016-01-01  2016      1    1            4 1 2016-01-02  2016      1    2            5 2 2016-01-03  2016      1    3            6 3 2016-01-04  2016      1    4            0 4 2016-01-05  2016      1    5            1 5 2016-01-06  2016      1    6            2 6 2016-01-07  2016      1    7            3 7 2016-01-08  2016      1    8            4 8 2016-01-09  2016      1    9            5 9 2016-01-10  2016      1   10            6

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