On Tue, 3 Jan 2006, Kasper Daniel Hansen wrote: > On Jan 3, 2006, at 9:36 AM, Brian D Ripley wrote: > >> I use save.image() or save(), which seem exactly what you are asking for. > > I have the (perhaps unsupported) impression that Ross wanted to save the > progress during the optim run. Since it spends most of its time in the > .Internal(optim(***)) call, save/save.image would not work.
It certainly does not! It is most likely spending time in the callbacks to evaluate the function/gradient. We have used save() to save the current information (e.g. current parameter values) from inside optim so a restart could be done, but then I have only once encountered someone running a single optimization for over a week: there normally are ways to speed things up. > /Kasper > >> On Mon, 2 Jan 2006, Ross Boylan wrote: >> >>> 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. >> >> -- >> Brian D. Ripley, [EMAIL PROTECTED] >> Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ >> University of Oxford, Tel: +44 1865 272861 (self) >> 1 South Parks Road, +44 1865 272866 (PA) >> Oxford OX1 3TG, UK Fax: +44 1865 272595 >> >> ______________________________________________ >> R-devel@r-project.org mailing list >> https://stat.ethz.ch/mailman/listinfo/r-devel > > -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel