[Rd] checkpointing

[Ross Boylan]

I would like to checkpoint some of my calculations in R, specifically
those using optim.  As far as I can tell, R doesn't have this facility,
and there seems to have been little discussion of it.

checkpointing is saving enough of the current state so that work can
resume where things were left off if, to take my own example, the system
crashes after 8 days of calculation.

My thought is that this could be added as an option to optim as one of
the control parameters.

I thought I'd check here to see if anyone is aware of any work in this
area or has any thoughts about how to proceed.  In particular, is save a
reasonable way to save a few variables to disk?  I could also make the
code available when/if I get it working.
-- 
Ross Boylan                                      wk:  (415) 514-8146
185 Berry St #5700                               ross at biostat.ucsf.edu
Dept of Epidemiology and Biostatistics           fax: (415) 514-8150
University of California, San Francisco
San Francisco, CA 94107-1739                     hm:  (415) 550-1062