[Rd] Bug in Sweave? -- scoping problem? (PR#8615)

[Friedrich.Leisch@tuwien.ac.at]

I will add it to the FAQ.

fritz

>>>>> On Sun, 19 Feb 2006 08:42:09 -0500,
>>>>> Duncan Murdoch (DM) wrote:

[...]

>       Code in chunks that produce pictures is executed several times.
>       First, to produce the output in the text.  And then once more
>       for *each* format in which the figure has to be produced.  I.e.,
>       if you want a PDF and a PostScript version of the figure, the
>       code is executed a total of three times.

  > Thanks, that's what caught me.  Is that a quote from the discussion, or 
  > from the docs somewhere?  It makes sense in hindsight, but it's not 
  > obvious ahead of time, so it should be stated fairly prominently in the 
  > docs.


  > Duncan Murdoch
  >> 
  >> All instances of this feature reported so far involved commands that
  >> produced random numbers and the poster was surprised that the output
  >> in the text and the figures differed (and that the two figures were
  >> different).
  >> 
  >> In your case the first execution of the code assigns the names to
  >> partytotal, sorts partytotal and produces the data.  On the next
  >> execution, when the picture is produced, partytotal is already sorted
  >> but you reassign the names.  Then the partytotal is sorted again and
  >> the plot is produced.  But that re-assigning of names lead to the
  >> disconnect between values and names.
  >> 
  >> Hope this helps.
  >> 
  >> Cheers,
  >> 
  >> Berwin
  >> 
  >> ========================== Full address ============================
  >> Berwin A Turlach                      Tel.: +61 (8) 6488 3338 (secr)   
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