Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
393 views
in Technique[技术] by (71.8m points)

r - Disabling the cat command

Suppose I have the following function:

## Just an example
f = function() { 
  for(i in 1:10000)
      cat(i)
  return(1)
}

When I call f() is there a way to stop cat printing to the screen (without altering the function in anyway)?

Reason behind this question

My students upload their R files. I then run the scripts and check to see if they are correct. Every so often, a student leaves in the cat command. This is especially irritating when it's in a long for loop

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

On Linux, you can use a sink() call to /dev/null(or to a temporary file on another OS, see ?tempfile) :

sink(file="/dev/null")
f()
sink()

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...