From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juan Subject: Re: [BABEL] Octave issues Date: Sun, 1 Aug 2010 19:55:56 -0300 Message-ID: <20100801225556.GV5569@soloJazz.com> References: <87iq45x06e.wl%ucecesf@ucl.ac.uk> <871vai42nz.fsf@stats.ox.ac.uk> <20100801200727.GT5569@soloJazz.com> <87hbje2cy5.fsf@stats.ox.ac.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from [140.186.70.92] (port=40833 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OfhRq-0000j3-T5 for emacs-orgmode@gnu.org; Sun, 01 Aug 2010 18:56:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OfhRp-0007VQ-Lw for emacs-orgmode@gnu.org; Sun, 01 Aug 2010 18:56:02 -0400 Received: from cpoproxy3-pub.bluehost.com ([67.222.54.6]:40613) by eggs.gnu.org with smtp (Exim 4.69) (envelope-from ) id 1OfhRp-0007V9-EF for emacs-orgmode@gnu.org; Sun, 01 Aug 2010 18:56:01 -0400 Content-Disposition: inline In-Reply-To: <87hbje2cy5.fsf@stats.ox.ac.uk> List-Id: "General discussions about Org-mode." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org Errors-To: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org To: Dan Davison Cc: emacs-orgmode@gnu.org, "d.tchin" On Sun, Aug 01, 2010 at 06:19:30PM -0400, Dan Davison wrote: > Juan writes: > Thanks very much. I've applied your patch with one minor change: > > (format "%s" (or var "nil")) > > However, is there a better way to receive an elisp nil value in octave? [] can be used for an empty matrix. What is the use-case for nil here? > > I'm not working with sessions, so I have not yet tested the original > > problem reported with 'org_babel_eoe' showing up as result. > > Sorry to pursue you for more help, but that problem is not limited to > sessions. A very simple demonstration of it is Apparently 'ans' won't help much; it only contains results of operations, not assignments. : The `ans' variable always contains the result of the last computation, : where the output wasn't assigned to any variable. The code `a = cos : (pi)' will assign the value -1 to the variable `a', but will not : change the value of `ans'. However, the code `cos (pi)' will set the : value of `ans' to -1. I cannot find an alternative way of getting the result from the last statement. You can assign to 'ans' however, so it could be an inconvenient requirement to either end the source block with a computation or with an assignment to 'ans'. Yuk! #+begin_src x = 42 ans = x #+end_src Another option, equally inconvenient, is to add a header option with the name of the variable to return (in case it is not 'ans'): #+begin_src :outvar x x = 42 3 * 3 # this doesn't matter #+end_src Another much more fragile option would be to actually parse the end of the code block looking for computation vs. assignment. This one will never work! Regards, .j.