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?
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:
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.
You could use an environmental variable. This can work with
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.