David and William, Thanks for your reply which make me know the concept of escape symbols.
As David guessed, I was trying to write a function which will accept a path cut from windows explorer. and as you know windows explorer uses "\". e.g., c:\temp\function.r I originally would like that the function is able to change the example path into "c:/temp/function.r" David's final comment seems to suggest this is impossible... If so, it is a limitation because I have to manually change "\" into "/" each time. But it is good to know this limitation. Correct me, if I misunderstand and there is no such a limitation. Thanks again. -Sean On Sun, Dec 13, 2009 at 5:26 PM, David Winsemius <dwinsem...@comcast.net>wrote: > > On Dec 13, 2009, at 5:11 PM, Sean Zhang wrote: > > Dear R-helpers: >> >> Hours ago, I asked how to replace a single forward slash with a double >> backward slash and recieved great help. Thanks again for all the repliers. >> >> In the meantime, I wonder how to replace a single backward slash with a >> double backward slash? >> >> e.g., I want change "c:\test" into "c:\\test" >> >> I tried the following but does not work. >> gsub("\\\","\\\\",) >> >> Can someone help? >> > > Your problem may be that you think there actually is a "\" in "c:\test". > There isn't: > > > grep("\\\\", "c:\test") # which would have found a true "\" > integer(0) > > It's an escaped "t", which is the tab character = "\t": > > > grep("\\\t", "c:\test") > [1] 1 > > cat("rr\tqq") > rr qq > > If your goal is to make file paths in Windows correctly, then you have two > choices: > > a) use doubled "\\"'s in the literal strings you type, or ... > b) use "/"'s > > So maybe you should explain what you are doing? We don't request that > background out of nosiness, but rather so we can give better answers > > -- > > David Winsemius, MD > Heritage Laboratories > West Hartford, CT > > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.