Re: [O] Selectively export RESULTS

[Matthew Landis]

On 3/2/2012 12:59 PM, Christophe Pouzat wrote:
> Matthew,
>
> I think that you're wrongly expecting babel's cache header argument to
> behave like the argument of the same name in Sweave code chunks. Babel
> will cache, in your case, the value of your code block evaluation and
> there is none in your first code block, therefore nothing gets cached by
> babel, try that instead:
>
> #+name: my-random-vector
> #+begin_src R :session :cache yes
> rnorm(100)
> #+end_src
>
> #+headers: :var x=my-random-vector
> #+headers: :results graphics :exports results :file hist.png
> #+begin_src R :session  :cache yes
> hist(x)
> #+end_src
>
> Does it work better? In that case you don't even need a session.
>
> Christophe
Christophe - thanks for the suggestion.  I haven't messed around much 
with variables passed between code blocks.  When I try this, R tells me 
that 'x' must be numeric.  When I query x in the R buffer, x is a 
data.frame.  So the second code block reads x in as a data.frame instead 
of a numeric vector.

For most purposes this would be OK (since a data.frame is the most usual 
outcome), but I'm reluctant to use this approach -- I'd like all of the 
variable passing to be in the R session.  Intuitively this seems 
simpler, less error prone, and more conducive to tangling later.  (Of 
course, I could be totally wrong - since I haven't really tried that 
approach).

M

--
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Matthew Landis, Ph.D.
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