Re: [O] are babel python sessions and inlined images incompatible?

[Sebastien Vauban]

Hi Rodrigo,

Rodrigo Amestica wrote:
> Sebastien Vauban wrote:
>>>> You don't need to explicitly specify a return when working with a
>>>> session. Either of the following should work.
>>>>
>>>>     #+BEGIN_SRC python :session test :file "images/test.png"
>>>>       from pylab import *
>>>>       plot(rand(10))
>>>>       savefig('images/test.png')
>>>>     #+END_SRC
>>>
>>> that does not quite work, I get no inlined image but the following line in
>>> the Messages buffer
>>>
>>> orgtbl-format-line: Wrong type argument: sequencep,
>>> <matplotlib\.lines\.Line2DError during redisplay: (wrong-type-argument
>>> arrayp nil)
>>
>> Try adding the `:results graphics' header argument...
>
> it does not help. Still same error. I'm using org-7.9.4 from tarball, in
> ob.el there is no 'graphics' option defined for :results.

Well, I *now* know it's not described in the Org manual...

  ╭──── http://lists.gnu.org/archive/html/emacs-orgmode/2013-03/msg01181.html
  │
  │ - :results graphics makes the list even longer, yes?  :-) I'm not
  │   sure that every language supports it and I don't believe it's
  │   currently in the manual.
  ╰────

Though, it's described in many different posts on this ML, and in some
tutorials on Worg...

  ╭──── http://orgmode.org/worg/org-contrib/babel/languages/ob-doc-R.html
  │
  │ If a :file filename.ext header argument is provided to an R source block, 
then
  │ the output from the source block will go to the named file. What that output
  │ is depends on the value of the :results header argument.
  │
  │ If the value is :results graphics then "base" graphics output is captured on
  │ disk, and a link to the graphics file is inserted into the Org Mode buffer 
(as
  │ is also the case with the graphics-only languages such as gnuplot, ditaa, 
dot,
  │ and asymptote.)
  ╰────

I thought it was a "core" option value for all general-purpose languages (e.g.
emacs-lisp, python, R, ruby, sh), required when your code block outputs a
graphics.

After checking, I only found it in those files:

--8<---------------cut here---------------start------------->8---
./ob-maxima.el:117:  (and (member "graphics" (cdr (assq :result-params params)))
./ob-octave.el:272:  (and (member "graphics" (cdr (assq :result-params params)))
./ob-R.el:234:  (and (member "graphics" (cdr (assq :result-params params)))
--8<---------------cut here---------------end--------------->8---

Maybe they are the only general-purpose languages able to output graphics? No,
wait, your example shows that python is also able to do so.

Then, I don't understand what that ":results graphics" option is not part of
python. Sorry not to be of more help...

Best regards,
  Seb

-- 
Sebastien Vauban