[FIXED] converting a pandas date to week number

Issue

I would like to extract a week number from data in a pandas dataframe.

The date format is datetime64[ns]

I have normalized the date to remove the time from it

df['Date'] = df['Date'].apply(pd.datetools.normalize_date)

so the date now looks like - 2015-06-17 in the data frame column

and now I like to convert that to a week number.

Thanks in advance

Solution

Just access the week attribute of Series.dt.isocalendar():

Example:

In [286]:
df['Date'].dt.isocalendar().week

Out[286]:
0    25
dtype: int64

In [287]:
df['Week_Number'] = df['Date'].dt.isocalendar().week
df

Out[287]:
        Date  Week_Number
0 2015-06-17           25

Answered By - EdChum