从日期列获取月份

Question

我需要从数据库的“ datetime”列中提取月份，并将其放在每一行的单独列中。我尝试了下面的代码以及许多其他代码。

df3['DatumTijdOverlijden'] = pd.to_datetime(df3['DatumTijdOverlijden'],
                                            format='"%Y-%m-%d %H:%M:%S"')

for x in df3['DatumTijdOverlijden']:
    a = 'DatumTijdOverlijden'
    datee = datetime.datetime.strptime(a, "%Y-%m-%d %H:%M:%S)
    df3.set_value(y, 'Month', datee)
    y+=1

Answer 1

您不需要执行此任务的循环。只需pd.Series.dt.month从datetime系列中提取属性即可。如果您需要将月份作为字符串，则可以使用pd.Series.dt.strtime方法。这里有些例子：

df = pd.DataFrame({'Date': ['05-01-2018', '02-20-2020']})

df['Date'] = pd.to_datetime(df['Date'])
df['Month'] = df['Date'].dt.month
df['Month-str'] = df['Date'].dt.strftime('%b')
df['Month-str-full'] = df['Date'].dt.strftime('%B')

print(df)

        Date  Month Month-str Month-str-full
0 2018-05-01      5       May            May
1 2020-02-20      2       Feb       February