我有一个非常大的数据集,我需要的时间间隔分成日期进行进一步的分析。
下面我的数据集的例子:
require(data.table)
RawDT = data.table(
TimeStampID = c("4"),
DateTimeFrom = c("2019-02-10 16:28:03"),
DateTimeTo = c("2019-02-12 02:04:03")
)
下面是期望的结果:
ResultDT = data.table(
ID = c("1","2","3"),
TimeStampID = c("4","4","4"),
DS = c("2019-02-10","2019-02-11","2019-02-12"),
TimeFrom = c("16:28:03","00:00:00","00:00:00"),
TimeTo = c("23:59:59","23:59:59","02:04:03")
)
任何人都可以指导我要使用哪个函数从RawDT实现ResultDT?
OK,这是重复的边缘 - 所以我鼓励版主,如果他们认为合适,这样做,关闭的话题,我会删除我的帖子。
不过,我也有类似(但不完全相同,这就是为什么我回答),与年初和年(here)的结束问题,@Jaap创造了一个伟大的(并且简洁!)解决方案,它也可以应用的逻辑在这里,例如:
library(data.table)
RawDT[, `:=` (DateTimeFrom = as.POSIXct(DateTimeFrom), DateTimeTo = as.POSIXct(DateTimeTo))]
RawDT[RawDT[, rep(.I, 1 + as.Date(DateTimeTo) - as.Date(DateTimeFrom))]
][, `:=` (DateTimeFrom = pmax(DateTimeFrom[1], as.POSIXct(paste0(as.Date(DateTimeFrom[1]) + 0:(.N-1), ' 00:00:00'))),
DateTimeTo = pmin(DateTimeTo[.N], as.POSIXct(paste0(as.Date(DateTimeTo[.N]) - (.N-1):0, ' 23:59:59'))))
, by = .(TimeStampID, rleid(DateTimeFrom))][]
我已经添加了另外一组您DT
只是为了测试功能:
RawDT = data.table(
TimeStampID = c("4", "5"),
DateTimeFrom = c("2019-02-10 16:28:03", "2019-03-15 12:28:03"),
DateTimeTo = c("2019-02-12 02:04:03", "2019-03-20 14:45:00")
)
和输出上面的代码将是:
TimeStampID DateTimeFrom DateTimeTo
1: 4 2019-02-10 16:28:03 2019-02-10 23:59:59
2: 4 2019-02-11 00:00:00 2019-02-11 23:59:59
3: 4 2019-02-12 00:00:00 2019-02-12 02:04:03
4: 5 2019-03-15 12:28:03 2019-03-15 23:59:59
5: 5 2019-03-16 00:00:00 2019-03-16 23:59:59
6: 5 2019-03-17 00:00:00 2019-03-17 23:59:59
7: 5 2019-03-18 00:00:00 2019-03-18 23:59:59
8: 5 2019-03-19 00:00:00 2019-03-19 23:59:59
9: 5 2019-03-20 00:00:00 2019-03-20 14:45:00