Python中的舍入日期时间对象

我试图在Python中舍入一个

datetime

对象，但遇到了一些问题。这里有很多关于舍入

datetime

的内容，但我找不到任何适合我需要的东西

我试图以

.now（）

为终点，获得15分钟间隔的日期范围。要获取我的

end=

，我需要：

pd.Timestamp.now（）.round（'15min'）

返回：

2019-08-16 11:15:00

这正是我想要的，但是，如果我在11:23运行它，它将返回我

2019-08-16 11:30:00

，而这并不是我想要的，我希望它四舍五入到

2019-08-16 11:15:00

，直到我们敲定11:30

有没有一个简单的方法让它四舍五入，因为我还没有找到答案，如果是这样的话

为任何帮助干杯使用：

对于测试：

df = pd.DataFrame({'dates':pd.date_range('2009-01-01', freq='T', periods=20)})

df['new'] = df['dates'].dt.floor('15min')
print (df)

0  2009-01-01 00:00:00 2009-01-01 00:00:00
1  2009-01-01 00:01:00 2009-01-01 00:00:00
2  2009-01-01 00:02:00 2009-01-01 00:00:00
3  2009-01-01 00:03:00 2009-01-01 00:00:00
4  2009-01-01 00:04:00 2009-01-01 00:00:00
5  2009-01-01 00:05:00 2009-01-01 00:00:00
6  2009-01-01 00:06:00 2009-01-01 00:00:00
7  2009-01-01 00:07:00 2009-01-01 00:00:00
8  2009-01-01 00:08:00 2009-01-01 00:00:00
9  2009-01-01 00:09:00 2009-01-01 00:00:00
10 2009-01-01 00:10:00 2009-01-01 00:00:00
11 2009-01-01 00:11:00 2009-01-01 00:00:00
12 2009-01-01 00:12:00 2009-01-01 00:00:00
13 2009-01-01 00:13:00 2009-01-01 00:00:00
14 2009-01-01 00:14:00 2009-01-01 00:00:00
15 2009-01-01 00:15:00 2009-01-01 00:15:00
16 2009-01-01 00:16:00 2009-01-01 00:15:00
17 2009-01-01 00:17:00 2009-01-01 00:15:00
18 2009-01-01 00:18:00 2009-01-01 00:15:00
19 2009-01-01 00:19:00 2009-01-01 00:15:00

df = pd.DataFrame({'dates':pd.date_range('2009-01-01', freq='T', periods=20)})

df['new'] = df['dates'].dt.floor('15min')
print (df)

0  2009-01-01 00:00:00 2009-01-01 00:00:00
1  2009-01-01 00:01:00 2009-01-01 00:00:00
2  2009-01-01 00:02:00 2009-01-01 00:00:00
3  2009-01-01 00:03:00 2009-01-01 00:00:00
4  2009-01-01 00:04:00 2009-01-01 00:00:00
5  2009-01-01 00:05:00 2009-01-01 00:00:00
6  2009-01-01 00:06:00 2009-01-01 00:00:00
7  2009-01-01 00:07:00 2009-01-01 00:00:00
8  2009-01-01 00:08:00 2009-01-01 00:00:00
9  2009-01-01 00:09:00 2009-01-01 00:00:00
10 2009-01-01 00:10:00 2009-01-01 00:00:00
11 2009-01-01 00:11:00 2009-01-01 00:00:00
12 2009-01-01 00:12:00 2009-01-01 00:00:00
13 2009-01-01 00:13:00 2009-01-01 00:00:00
14 2009-01-01 00:14:00 2009-01-01 00:00:00
15 2009-01-01 00:15:00 2009-01-01 00:15:00
16 2009-01-01 00:16:00 2009-01-01 00:15:00
17 2009-01-01 00:17:00 2009-01-01 00:15:00
18 2009-01-01 00:18:00 2009-01-01 00:15:00
19 2009-01-01 00:19:00 2009-01-01 00:15:00