(This article was first published on macsci, and kindly contributed to R-bloggers)

We developed two scripts: one for setting the working directory of R directly, and one for adding setwd('/the/directory/of/your/current/document/') to your current document.
If you would like to use them, download the scripts below, and place them in ~/Library/Application Support/TextWrangler/Scripts/, and assign shortcuts using TW's Window -> Palettes -> Scripts menu.
Download the scripts here:
the script to set R's working directory directly
the script to add the setwd command to your document
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