Kepler

The RExpression actor provides a basic, easy-to-use interface between Kepler and
R. It does not, however, handle all R datatypes. (It does allow number, string,
array, and dataframe inputs and all of these but dataframe outputs.) It also
depends on starting up a new instance of R each time it is called. And the
conversions are all string-based, which is inefficient.

There may be the need for a more complete implementation of an R actor, perhaps
using a remote R server, that would remain running, and carry out Kepler/R and
R/Kepler conversions more efficiently.

Similarly, R graphics is integrated into Kepler via image files (jpegs). A more
direct method for getting R graphics into Kepler would be useful.