我有一个包含两个参数(日期和数值)的data.table
,现在我想计算每分钟(或每15分钟)的平均值。
- 我一开始认为应该将日期分成小时和分钟
- 然后计算时间间隔内的平均值
但我真的不知道该怎么做,也许你会有想法
例如,这是简单的数据。
date Value
2015-07-01 00:00:23 1.83
2015-07-01 00:00:24 1.68
2015-07-01 00:00:25 1.29
2015-07-01 00:00:40 14.23
2015-07-01 00:00:41 0.96
2015-07-01 00:00:46 4.93
2015-07-01 00:01:12 26.44
2015-07-01 00:02:02 49.66
2015-07-01 00:02:05 3.00
2015-07-01 00:02:08 3.19
2015-07-01 00:02:27 19.42
2015-07-01 00:02:32 4.44
2015-07-01 00:02:45 12.77
2015-07-01 00:02:49 4.44
2015-07-01 00:03:40 50.71
2015-07-01 00:03:50 10.64
2015-07-01 00:03:52 1.18
2015-07-01 00:03:52 0.99
2015-07-01 00:03:54 1.32
2015-07-01 00:03:56 2.20
这里有一段生成测试数据的代码:
dd <- data.table(date = c("2015-07-01 00:00:23", "2015-07-01 00:00:24", "2015-07-01 00:00:25","2015-07-01 00:00:40", "2015-07-01 00:00:46","2015-07-01 00:01:12","2015-07-01 00:02:02","2015-07-01 00:02:08","2015-07-01 00:02:27","2015-07-01 00:02:32","2015-07-01 00:02:45","2015-07-01 00:02:49","2015-07-01 00:03:40","2015-07-01 00:03:50","2015-07-01 00:03:52","2015-07-01 00:03:54","2015-07-01 00:03:56"),
value = c(1.83,1.68,1.29,14.23,0.96,4.93,26.44,3.00,3.19,19.42,4.44,50.71,10.64,1.18,0.99,1.32,2.20))