+(defun org-babel-R-graphical-output-file (params)
+ "Name of file to which R should send graphical output."
+ (and (member "graphics" (cdr (assq :result-params params)))
+ (cdr (assq :file params))))
+
+(defvar org-babel-R-graphics-devices
+ '((:bmp "bmp" "filename")
+ (:jpg "jpeg" "filename")
+ (:jpeg "jpeg" "filename")
+ (:tikz "tikz" "file")
+ (:tiff "tiff" "filename")
+ (:png "png" "filename")
+ (:svg "svg" "file")
+ (:pdf "pdf" "file")
+ (:ps "postscript" "file")
+ (:postscript "postscript" "file"))
+ "An alist mapping graphics file types to R functions.
+
+Each member of this list is a list with three members:
+1. the file extension of the graphics file, as an elisp :keyword
+2. the R graphics device function to call to generate such a file
+3. the name of the argument to this function which specifies the
+ file to write to (typically \"file\" or \"filename\")")
+