[R] loading a file in R in mac OS X

[Marc Schwartz]

On Jul 16, 2009, at 6:32 AM, caballo wrote:

>
> Hello,
>
> Please forgive me that this question is so basic, but i have not  
> been able
> to find a solution in any of the basic R introductions, in the R  
> wiki, or in
> the stats textbook i'm using to learn R. I run R on a macintosh, and  
> i have
> not been able to load any data files yet. For instance, if I have a  
> data
> table in a file called schools.txt on my desktop, i've been trying  
> to load
> the table as such:
>
>> schools <-
>> read.table("c:\harddrivename\users\username\desktop\schools.txt",
>> header=T,row.names=1)
>
> (obviously for the purposes of posting in this forum i've entered  
> generic
> folder names.)
>
> No matter how i ammend the path, i get the following error message:
>
> Error in file(file, "r") : cannot open the connection
> In addition: Warning message:
> In file(file, "r") :
> cannot open file 'c:\harddrivename\users\username\desktop 
> \schools.txt':
> No such file or directory.
>
> I'm guessing that there's a different way to enter the path name on a
> macintosh?
>
> Thanks for your help!



You are using a Windows based file path and on Windows, you would need  
to double the backslashes. See:

   http://cran.r-project.org/bin/windows/base/rw-FAQ.html#R-can_0027t-find-my-file

On OSX, there is no "C:" drive and you would use forward slashes. The  
typical file path on OSX would be:

   /Users/username/Desktop/schools.txt

If you are using the OSX GUI (R.app) you may also want to review the  
OSX FAQ:

   http://cran.r-project.org/bin/macosx/RMacOSX-FAQ.html#R_002eapp

There is a Mac/OSX specific R e-mail list, which you should consider  
subscribing to. More info:

   https://stat.ethz.ch/mailman/listinfo/r-sig-mac

As it sounds like you are new to Macs and will be spending more time  
on them, you might also consider picking up a good Intro to OSX book,  
of which there are many. Check your local bookstore or Amazon. Pogue's  
books have generally worked well for folks:

   http://www.amazon.com/Mac-OS-Leopard-Missing-Manual/dp/059652952X
   http://www.amazon.com/Switching-Mac-Missing-Manual-Leopard/dp/0596514123/


HTH,

Marc Schwartz