我有一个试图解析的文本文件，并将信息放入数据框。在每个“事件”中，可能有也可能没有注释。但是，注释可以跨越各种行。我需要将每个事件的注释连接为一个字符串，以存储在数据框的一列中。
ID: 20470
Version: 1
notes:
ID: 01040
Version: 2
notes:
The customer was late.
Project took 20 min. longer than anticipated
Work was successfully completed
ID: 00000
Version: 1
notes:
Customer was not at home.
ID: 00000
Version: 7
notes:
Fax at 2:30 pm
Called but no answer
Visit home no answer
Left note on door with call back number
Made a final attempt on 12/5/2013
closed case on 12/10 with nothing resolved
例如，对于第三次事件，注释应为一个长字符串：“客户迟到。项目花费了比预期工作成功完成要长20分钟的时间”，然后将其存储到数据框。
对于每个事件，我知道注释跨越多少行。
答案 0 :(得分：0)
这样的事情（实际上，您会更快乐，并且可以自己了解更多信息，我只是在两个任务之间拖延时间）：
x <- readLines("R/xample.txt") # you'll probably read it from a file
ids <- grep("^ID:", x) # detecting lines starting with ID:
versions <- grep("^Version:", x)
notes <- grep("^notes:", x)
nStart <- notes + 1 # lines where the notes start
nEnd <- c(ids[-1]-1, length(x)) # notes end one line before the next ID: line
ids <- sapply(strsplit(x[ids], ": "), "[[", 2)
versions <- sapply(strsplit(x[versions], ": "), "[[", 2)
notes <- mapply(function(i,j) paste(x[i:j], collapse=" "), nStart, nEnd)
df <- data.frame(ID=ids, ver=versions, note=notes, stringsAsFactors=FALSE)
> dput(x)
c("ID: 20470", "Version: 1", "notes: ", " ", " ", "ID: 01040",
"Version: 2", "notes: ", " The customer was late.", "Project took 20 min. longer than anticipated",
"Work was successfully completed", "", "ID: 00000", "Version: 1",
"notes: ", " Customer was not at home.", "", "ID: 00000", "Version: 7",
"notes: ", " Fax at 2:30 pm", "Called but no answer", "Visit home no answer",
"Left note on door with call back number", "Made a final attempt on 12/5/2013",
"closed case on 12/10 with nothing resolved ")