在 r 中将文本行写入文件

In the R scripting language, how do I write lines of text, e.g. the following two lines

Hello
World

to a file named "output.txt"?

转载于:https://stackoverflow.com/questions/2470248/write-lines-of-text-to-a-file-in-r

fileConn<-file("output.txt")
writeLines(c("Hello","World"), fileConn)
close(fileConn)

Actually you can do it with sink():

sink("outfile.txt")
cat("hello")
cat("\n")
cat("world")
sink()

hence do:

file.show("outfile.txt")
# hello
# world

I would use the cat() command as in this example:

> cat("Hello",file="outfile.txt",sep="\n")
> cat("World",file="outfile.txt",append=TRUE)

You can then view the results from with R with

> file.show("outfile.txt")
hello
world

What's about a simple writeLines()?

txt <- "Hallo\nWorld"
writeLines(txt, "outfile.txt")

or

txt <- c("Hallo", "World")
writeLines(txt, "outfile.txt")

The ugly system option

ptf <- function (txtToPrint,outFile){system(paste(paste(paste("echo '",cat(txtToPrint),sep = "",collapse = NULL),"'>",sep = "",collapse = NULL),outFile))}
#Prints txtToPrint to outFile in cwd. #!/bin/bash echo txtToPrint > outFile

To round out the possibilities, you can use writeLines() with sink(), if you want:

> sink("tempsink", type="output")
> writeLines("Hello\nWorld")
> sink()
> file.show("tempsink", delete.file=TRUE)
Hello
World

To me, it always seems most intuitive to use print(), but if you do that the output won't be what you want:

...
> print("Hello\nWorld")
...
[1] "Hello\nWorld"

You could do that in a single statement

cat("hello","world",file="output.txt",sep="\n",append=TRUE)

1.Using file argument in cat.

 cat("Hello World", file="filename")

2.Use sink function to redirect all output from both print and cat to file.

 sink("filename")                     # Begin writing output to file
 print("Hello World")
 sink()                               # Resume writing output to console

NOTE: The print function cannot redirect its output, but the sink function can force all output to a file.

3.Making connection to a file and writing.

con <- file("filename", "w")
cat("Hello World", file=con)
close(con)

Based on the best answer:

file <- file("test.txt")
writeLines(yourObject, file)
close(file)

Note that the yourObject needs to be in a string format; use as.character() to convert if you need.

But this is too much typing for every save attempt. Let's create a snippet in RStudio.

In Global Options >> Code >> Snippet, type this:

snippet wfile
    file <- file(${1:filename})
    writeLines(${2:yourObject}, file)
    close(file)

Then, during coding, type wfile and press Tab.

I suggest:

writeLines(c("Hello","World"), "output.txt")

It is shorter and more direct than the current accepted answer. It is not necessary to do:

fileConn<-file("output.txt")
# writeLines command using fileConn connection
close(fileConn)

Because the documentation for writeLines() says:

If the con is a character string, the function calls file to obtain a file connection which is opened for the duration of the function call.

# default settings for writeLines(): sep = "\n", useBytes = FALSE
# so: sep = "" would join all together e.g.