从日期时间获取日期和小时作为新列

Question

我在从CSV文件导入的熊猫数据框中有以下列。我想添加两列，分别包含小时和星期几。

输入：

+-------------------+
|        date       |
+-------------------+
|2018/08/26  7:30:26|
+-------------------+
|2018/05/12  8:10:26|
+-------------------+
|2018/11/16 14:36:26|
+-------------------+
|2018/12/06 17:40:26|
+-------------------+

输出必须为：

+-------------------+----------+------+
|    date-time      |  date    | hour |
+-------------------+----------+------+
|2018/08/26  7:30:26|2018/08/26| 7    |
+-------------------+----------+------+
|2018/05/12  8:10:26|2018/05/12| 8    |
+-------------------+----------+------+
|2018/11/16 14:36:26|2018/11/16|14    |
+-------------------+----------+------+
|2018/12/06 17:40:26|2018/12/06|17    |
+-------------------+----------+------+

Answer 1

您可以使用dt访问器从日期时间值中获取date和hour：

df.date = pd.to_datetime(df.date)
df = df.rename(columns = {'date':'datetime'})
df.assign(date = df.date.dt.date, hour = df.date.dt.hour)

         datetime        date       hour
0 2018-08-26 07:30:26  2018-08-26     7
1 2018-05-12 08:10:26  2018-05-12     8
2 2018-11-16 14:36:26  2018-11-16    14
3 2018-12-06 17:40:26  2018-12-06    17