I use R under Windows on several machines.
I know you can set the working directory from within an R script, like this
setwd("C:/Documents and Settings/username/My Documents/x/y/z")
... but then this breaks the portability of the script. It's also annoying to have to reverse all the slashes (since Windows gives you backslashes)
Is there a way to start R in a particular working directory so that you don't need to do this at the script level?
If you're using Emacs/ESS, this isn't a problem. I navigate to the directory where my R script is located, open it, then start an R ESS process. An R console pops up with the current directory as R's working directory.
If you haven't converted to Emacs/ESS, I recommend it. (Though to prevent a flame war, I also note there are similar options for Vi users.)
Hope that helps.
You could use an environmental variable. This can work with Sys.getenv() and Sys.setenv(). For instance:
> Sys.setenv(R_TEST="testit")
> Sys.getenv("R_TEST")
R_TEST
"testit"
If you sent the variable in your script, you should be able to access it from within, and then call setwd() on that output.
You should copy shortcut to R (R.lnk file) to desire folder. Then in "Properties" (right mouse button -> last option) delete anything in field "Start in..." in second tab ("Shortcut"?). If you start R with this shortcut working directory will be that one where the shortcut is.
I don't have english version of Windows so I'm not sure about field names, but they should be easy to find.
Similar questions were in R-windows-faq:
2.10 How can I keep workspaces for different projects in different directories?
2.14 What are HOME and working directories?
In 2.14 is mentioned that
The working directory is the directory from which Rgui or Rterm was launched, unless a shortcut was used when it is given by the `Start in' field of the shortcut's properties.
Save your workspace to the desired directory and thereafter you just open the workspace from Windows explorer.
Just a detail: instead of reversing the slashes as you say, just add another backslash. Two of these \\ works the same way as one of these /. That makes it at least a little easier.
I put the following in front of my scripts and it allows me to work across my computers.
setwd(path.expand("~/path/to/working/directory/") )
where ~ is = to your home directory.
Sys.setenv(HOME = "path") or Sys.setenv(R_USER = "path") can both set the home directory.
In my case, I work on several windows boxes, each have fairly different directory structures, but by setting the home directory properly I can sync code between computers and have them run properly on each one since where I run my R projects have similar directory structures.
Put a shortcut for the R gui into your desired directory. Right-click and look at the shortcut properties. Delete the entry for "Start In" and click OK. When you launch the R gui from this shortcut the default directory will be the folder from which you have launched. Copy/paste this shortcut wherever you desire.