From rmh at temple.edu  Wed Sep  6 01:40:18 2006
From: rmh at temple.edu (Richard M. Heiberger)
Date: Tue,  5 Sep 2006 19:40:18 -0400 (EDT)
Subject: [Rd] Two submitted packages
Message-ID: <20060905194018.BHI53591@po-d.temple.edu>

From: Prof Brian Ripley
> There is no '2.4.1', and your R-devel is not very recent.

Apologies on the typo and the two-week old 2.4.0dev.

I just downloaded
   version 2.4.0 Under development (unstable) (2006-09-04 r39086)


1.
> You set cpv$clip <- "off" and the internal code assumes that it is logical 
> (as the message says).  I can't find any documentation to support your 
> code: if there is some please report it to the maintainer of grid (Paul 
> Murrell).

The documentation for "off" comes from ?viewport that is part of 2.4.0dev.
> installed.packages()["grid",]
                           Package                            LibPath 
                            "grid" "C:/PROGRA~1/R/R-24~1.0DE/library" 
                           Version                           Priority 
                           "2.4.0"                             "base" 
                            Bundle                           Contains 
                                NA                                 NA 
                           Depends                            Imports 
                       "grDevices"                                 NA 
                          Suggests                              Built 
                         "lattice"                            "2.4.0" 

clip
    One of "on", "inherit", or "off", indicating whether to clip to the
    extent of this viewport, inherit the clipping region from the parent
    viewport, or turn clipping off altogether. For back-compatibility, a
    logical value of TRUE corresponds to "on" and FALSE corresponds to
    "inherit".

The above description of clip is identical to the description in
?viewport in the released 2.3.1.


I still get the same error in 2.4.0dev that did not appear in 2.3.1
and it still looks to me like this is an equally valid statement in both
versions of R.
>  Error in grid.Call.graphics("L_setviewport", pvp, TRUE) : 
>          LOGICAL() can only be applied to a 'logical', not a 'character'
>  >

I think something needs to be changed to make the documentation and the
program consistent.  I like the documentation, with the three options
for clipping, and hope to see the program changed to match it.


2.
> > ## Question 1.  How do I place a trace() on grid.Call.graphics to make
> > ## it stop and give me a traceback.
> Not sure why you want to do that, as traceback() works here.
... as does options(error=recover).

I was interested in the argument
    trace(..., exit=recover)
I see now that
    options(error=recover)
does exactly what I want.  That is the incantation I was looking for.
Thank you.




[Rd] Two submitted packages
Richard M. Heiberger