在R中的每一行文本之间插入带有递增编号的新行

Question

I am trying to run a script in Rthat gets a load of text, finds the unique lines, lists them and then inserts a new line between each line and sequentially numbers them as follows:

The cat sat on the mat
The cat sat on the mat
The cat sat on the mat
The bat said drat
The bat said drat
The gnat wore a hat

becomes....
 >1
 The cat sat on the mat
 >2
 The bat said drat
 >3
 The gnat wore a hat

The script I have so far just gets the unique lines

fileConn<-file("/Users/bilbo/Desktop/output.txt")
longlist <- readLines(file.choose())

lvls1 <- unique(longlist)
writeLines(lvls1, fileConn)
close(fileConn)
View(lvls1)

Please help.....!

Insert new line with incrementing number between each line of text in R

Answer 1

How about

#Test data
tc<-textConnection("The cat sat on the mat
The cat sat on the mat
The cat sat on the mat
The bat said drat
The bat said drat
The gnat wore a hat")

longlist <- readLines(tc)
close(tc)

fileConn<-file("/Users/bilbo/Desktop/output.txt")
lvls1 <- unique(longlist)
cat(paste0(">", seq_along(lvls1), "\n", lvls1, collapse="\n"), file=fileConn)
close(fileConn)

Here I wrote to a different file with a set name.

Answer 2

Another similar way:

tc <- "The cat sat on the mat
The cat sat on the mat
The cat sat on the mat
The bat said drat
The bat said drat
The gnat wore a hat"

stuff <- unique(scan(text=tc,sep="\n",what="character"))
# for your code:
# stuff <- unique(scan(file="filename.txt",sep="\n",what="character"))
cat(rbind(paste0(">",seq_along(stuff)),stuff),sep="\n")

#>1
#The cat sat on the mat
#>2
#The bat said drat
#>3
#The gnat wore a hat