Re: [Rd] data frame subset patch, take 2

From: Vladimir Dergachev <>
Date: Tue 19 Dec 2006 - 23:18:43 GMT

On Saturday 16 December 2006 4:41 pm, Martin Maechler wrote:
> Correction: the problems show on both platforms;
> one is in mgcv, gam(), an error in [[ <- -- pretty clearly linked to your
> changes but not reproducible when tried isolatedly
> interactively,
> the other one is a seg.fault "memory not mapped" when running
> the example
> > nuke.boot <- boot(,, R=999, m=1,
> +,
> MM> My guess: typically when dealing with model.frames (which
> MM> internally are "just" data frames with a particular "terms"
> attribute) MM> but the problems are not reproducible when run
> interactively. MM> It may really be that .subset() and .subset2() are
> sometimes MM> used in cases they should not be in your new code; or they
> even have a bug that MM> is not triggered unless by using them in the new
> context of [.data.frame
> MM> So I'm sorry, but we might have to wait for a "take 3"
> MM> or rather try to find the problem with your patch.
> MM> Maybe you can try yourself?

Hi Martin,

   thank you very much for the feedback !

   Of course, there is going to be take 3 :)

   I have reproduced your tests with slightly different results: boot.Rcheck fails, stats.Rcheck segfaults, cluster.Rcheck fails.

   More importantly I was able to reproduce the problem interactively with boot.Rcheck. When interactive I found that the issue has random outcomes - sometimes it segfaults and sometimes it produces this:

  1. boot.Rcheck fails with

> nuke.boot <- boot(,, R=999, m=1,
+, Error: incompatible types (from NULL to list) in [[ assignment Execution halted

    but does not segfault. Other times it errors out in different places or goes through fine. On one occasion I observed a very interesting behaviour - the R console looked like it was completely confused about which functions are being called and about arguments passed to them.

   After some tinkering, I realized that, perhaps, the problem is with me adding .subassign and .subassign2 functions and this somehow interfering with saved workspaces. So I did make clean (after updating SVN) and the problem appears to be gone.

   Could you try dong make clean && make on your installation and reporting the results ?

                              thank you very much !

                                           Vladimir Dergachev

______________________________________________ mailing list Received on Wed Dec 20 19:08:21 2006

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.1.8, at Wed 20 Dec 2006 - 13:31:00 GMT.

Mailing list information is available at Please read the posting guide before posting to the list.