R:根据观察窗口的特定分钟数内的时间对数据框进行子集

Question

假设我有一个包含开始和结束时间列、一个测量列和一个测量时间列的数据框，如下所示:

     start         end    value                time
   9:01:00     9:02:00     30.6  2013-03-25 9:05:00
   9:01:00     9:02:00     30.8  2013-03-25 9:15:00
   9:46:00     9:46:00     28.2  2013-03-25 9:43:00
   9:46:00     9:46:00     28.9  2013-03-25 9:53:00
  10:54:00    10:59:00     13.4 2013-03-25 10:56:00
  10:54:00    10:59:00     13.8 2013-03-25 11:56:00

如何对该数据框进行子集化以仅包含时间列在开始和结束时间或开始时间前十分钟和结束时间后十分钟内的行。我任意选择十分钟，并想知道如何在开始和结束时间之前和之后的任何时间内执行此操作。

结果数据框如下:

     start         end    value                time
   9:01:00     9:02:00     30.6  2013-03-25 9:05:00
   9:46:00     9:46:00     28.2  2013-03-25 9:43:00
   9:46:00     9:46:00     28.9  2013-03-25 9:53:00
  10:54:00    10:59:00     13.4 2013-03-25 10:56:00

除了从开始/结束列条目中减去/添加 x 分钟数，然后根据时间列是否落在这些展开的窗口之间进行子集设置之外，还有其他方法可以做到这一点吗？

目前，我已将时间列转换为 POSIXlt 格式。不幸的是，这将今天的日期指定为开始和结束列中的时间。

这是第一个数据帧的 dput:

structure(list(start = structure(list(sec = c(0, 0, 0, 0, 0, 
0), min = c(1L, 1L, 46L, 46L, 54L, 54L), hour = c(9L, 9L, 9L, 
9L, 10L, 10L), mday = c(7L, 7L, 7L, 7L, 7L, 7L), mon = c(7L, 
7L, 7L, 7L, 7L, 7L), year = c(113L, 113L, 113L, 113L, 113L, 113L
), wday = c(3L, 3L, 3L, 3L, 3L, 3L), yday = c(218L, 218L, 218L, 
218L, 218L, 218L), isdst = c(1L, 1L, 1L, 1L, 1L, 1L)), .Names = c("sec", 
"min", "hour", "mday", "mon", "year", "wday", "yday", "isdst"
), class = c("POSIXlt", "POSIXt")), end = structure(list(sec = c(0, 
0, 0, 0, 0, 0), min = c(2L, 2L, 46L, 46L, 59L, 59L), hour = c(9L, 
9L, 9L, 9L, 10L, 10L), mday = c(7L, 7L, 7L, 7L, 7L, 7L), mon = c(7L, 
7L, 7L, 7L, 7L, 7L), year = c(113L, 113L, 113L, 113L, 113L, 113L
), wday = c(3L, 3L, 3L, 3L, 3L, 3L), yday = c(218L, 218L, 218L, 
218L, 218L, 218L), isdst = c(1L, 1L, 1L, 1L, 1L, 1L)), .Names = c("sec", 
"min", "hour", "mday", "mon", "year", "wday", "yday", "isdst"
), class = c("POSIXlt", "POSIXt")), value = c(30.6, 30.8, 28.2, 
28.9, 13.4, 13.8), time = structure(list(sec = c(0, 0, 0, 0, 
0, 0), min = c(5L, 15L, 43L, 53L, 56L, 56L), hour = c(9L, 9L, 
9L, 9L, 10L, 11L), mday = c(25L, 25L, 25L, 25L, 25L, 25L), mon = c(2L, 
2L, 2L, 2L, 2L, 2L), year = c(113L, 113L, 113L, 113L, 113L, 113L
), wday = c(1L, 1L, 1L, 1L, 1L, 1L), yday = c(83L, 83L, 83L, 
83L, 83L, 83L), isdst = c(1L, 1L, 1L, 1L, 1L, 1L)), .Names = c("sec", 
"min", "hour", "mday", "mon", "year", "wday", "yday", "isdst"
), class = c("POSIXlt", "POSIXt"))), .Names = c("start", "end", 
"value", "time"), row.names = c(NA, -6L), class = "data.frame")

这是第二个数据帧的 dput

structure(list(start = structure(list(sec = c(0, 0, 0, 0), min = c(1L, 
46L, 46L, 54L), hour = c(9L, 9L, 9L, 10L), mday = c(7L, 7L, 7L, 
7L), mon = c(7L, 7L, 7L, 7L), year = c(113L, 113L, 113L, 113L
), wday = c(3L, 3L, 3L, 3L), yday = c(218L, 218L, 218L, 218L), 
    isdst = c(1L, 1L, 1L, 1L)), .Names = c("sec", "min", "hour", 
"mday", "mon", "year", "wday", "yday", "isdst"), class = c("POSIXlt", 
"POSIXt")), end = structure(list(sec = c(0, 0, 0, 0), min = c(2L, 
46L, 46L, 59L), hour = c(9L, 9L, 9L, 10L), mday = c(7L, 7L, 7L, 
7L), mon = c(7L, 7L, 7L, 7L), year = c(113L, 113L, 113L, 113L
), wday = c(3L, 3L, 3L, 3L), yday = c(218L, 218L, 218L, 218L), 
    isdst = c(1L, 1L, 1L, 1L)), .Names = c("sec", "min", "hour", 
"mday", "mon", "year", "wday", "yday", "isdst"), class = c("POSIXlt", 
"POSIXt")), value = c(30.6, 28.2, 28.9, 13.4), time = structure(list(
    sec = c(0, 0, 0, 0), min = c(5L, 43L, 53L, 56L), hour = c(9L, 
    9L, 9L, 10L), mday = c(25L, 25L, 25L, 25L), mon = c(2L, 2L, 
    2L, 2L), year = c(113L, 113L, 113L, 113L), wday = c(1L, 1L, 
    1L, 1L), yday = c(83L, 83L, 83L, 83L), isdst = c(1L, 1L, 
    1L, 1L)), .Names = c("sec", "min", "hour", "mday", "mon", 
"year", "wday", "yday", "isdst"), class = c("POSIXlt", "POSIXt"
))), .Names = c("start", "end", "value", "time"), row.names = c(NA, 
-4L), class = "data.frame")

Answer 1

基于@EliGurarie 的回答:

#dat <- ....see original question

将时间转换为 POSIX表示和做数学:

datestem <- as.character(as.Date(dat$time))
dat$start <- as.POSIXct(paste(datestem,format(dat$start,"%H:%M:%S")))
dat$end <- as.POSIXct(paste(datestem,format(dat$end,"%H:%M:%S")))

dat[
     with(
      dat,
      difftime(start,time,units="mins") > -10 &
      difftime(end,time,units="mins") < 10
     ),
   ]

或者，使用一些舍入和一些中间变量:

min10 <- 10/(60*24)
ds <- difftime(dat$start,dat$time,units="days")
ds <- dd - round(dd) 
de <- difftime(dat$end,dat$time,units="days")
de <- de - round(de) 

dat[ds > -min10 & de < min10,]