r - 完成序列列并填写行

Question

我从一个数据集开始，该数据集具有数字列(在我的例子中是时间，但采用数字格式)、时间戳的特定事件和 ID。我希望运行一些代码来扩展数据框以填充数字序列，同时复制事件列(和任何其他相关列)。我想通过 ID 运行它，所以我不会填补 ID 之间的空白。

这是我开始使用的数据的一个简化示例。我想分别为每个 ID 填充“值”列的序列，用每个“事件”的第一行中的数据完成每个新行。

 a<-c("162", "164", "169", "171", "174", "188", "191", "198","200")
b<-c("start1","end1","start2", "event", "end2", "start1", "end1", "start2", "end2")
c<-c("A","A","A", "A", "A", "B", "B", "B", "B")

original<-data.table(value = a, event = b, ID = c)

这是我最终目标的重构:

agoal<-c(seq(from = 162, to = 174), seq(from = 188, to = 200))
bgoal<-c("start1","start1","end1","end1", "end1", "end1", "end1",
     "start2", "start2",  "event", "end2","end2", "end2", 
     "start1", "start1", "start1", "end1", "end1", "end1", "end1", "end1", "end1", "end1",
     "start2", "start2","end2")
cgoal<-c(rep("A",13), rep("B",13))

goal<-data.table(value = agoal, event = bgoal, ID = cgoal)

抱歉，如果这不是很清楚!

Answer 1

我们可以使用 tidyr 包中的 complete 和 fill:首先使用tpye.convert(as.is=TRUE)将numeric赋给value

library(dplyr)
library(tidyr)

original %>% 
  type.convert(as.is=TRUE) %>% 
  group_by(ID) %>% 
  complete(value = first(value):max(value)) %>% 
  fill(event) 

输出:

    value  event ID
 1:   162 start1  A
 2:   163 start1  A
 3:   164   end1  A
 4:   165   end1  A
 5:   166   end1  A
 6:   167   end1  A
 7:   168   end1  A
 8:   169 start2  A
 9:   170 start2  A
10:   171  event  A
11:   172   end2  A
12:   173   end2  A
13:   174   end2  A
14:   188 start1  B
15:   189 start1  B
16:   190 start1  B
17:   191   end1  B
18:   192   end1  B
19:   193   end1  B
20:   194   end1  B
21:   195   end1  B
22:   196   end1  B
23:   197   end1  B
24:   198 start2  B
25:   199 start2  B
26:   200   end2  B