我有两个数据框df1和df2.
我试图找出执行的映射，对于在每一行的最好方式df1，我想搜索匹配（id，time_by_hour）中df2，然后填入相应的值df2回df1。
下面是df1_final我希望它最终看起来的样子。
先感谢您！
df1
Out[100]:
id time_by_min time_by_hour value
0 a 2017-06-30 01:25:00.000 2017-06-30 02:00:00 NaN
1 a 2017-06-30 01:36:32.308 2017-06-30 02:00:00 NaN
2 a 2017-06-30 02:25:00.000 2017-06-30 03:00:00 NaN
3 a 2017-06-30 02:36:32.308 2017-06-30 03:00:00 NaN
4 b 2017-06-30 01:25:00.000 2017-06-30 02:00:00 NaN
5 b 2017-06-30 01:36:32.308 2017-06-30 02:00:00 NaN
6 b 2017-06-30 02:25:00.000 2017-06-30 03:00:00 NaN
df2
Out[101]:
id …