Re: Ideas for auto BSX

[Juan Pablo Carbajal]

On Wed, Dec 14, 2011 at 7:00 PM, John W. Eaton <address@hidden> wrote:
> On 14-Dec-2011, Juan Pablo Carbajal wrote:
>
> | 2011/12/14 Jordi Gutiérrez Hermoso <address@hidden>:
> | > 2011/12/14 Judd Storrs <address@hidden>:
> | >> 2011/10/1 Jordi Gutiérrez Hermoso <address@hidden>:
> | >>> As I've said before, I don't see "Matlab compatibility" to be anything
> | >>> more than source compatibility. If it runs in Matlab, it should run in
> | >>> Octave and produce almost the same result (perhaps slight variation in
> | >>> graphics is acceptable, for example). I don't see making everything in
> | >>> Octave working and looking exactly like Matlab to be the goal. We
> | >>> already have lots of other nice Octave-only language features (e.g.
> | >>> being able to define functions interactively without needing a
> | >>> separate file for each or being able to index temporaries), and that's
> | >>> not lack of Matlab compatibility.
> | >>
> | >> One thing that just occurred to me is: does it become much more
> | >> difficult to automatically translate octave code into code that will
> | >> run in matlab?
> | >
> | > Octave already has a bunch of code that is difficult to automatically
> | > translate into Matlab. Unwind-protect? Functions defined in script
> | > files as opposed to function files? Generating intermediate variables
> | > when indexing temporaries?
> | >
> | > - Jordi G. H.
> |
> | Jordi I do like the auto bsx, but I agree with Judd. It may create
> | more problems in translation.
> | I am a supporter for having a clear translation table between Octave
> | and ML, I collaborate a lot with people that only use ML, and so far
> | things are going good with a small translation table, but I think, as
> | Judd, that this case would be not so easily detected.
> | One thing is to have different code (all the cases you mentioned) that
> | can be easily identified (even automatically), but how would you
> | recognize
> | a - b
> | to be
> | bsxfun(@minus,a,b)?
> |
> | Only a parser with access to the sizes of the variables will be able
> | to translate that.
>
> The parser has no knowledge of the sizes of variables.  Those are only
> known when the code is interpreted, and they can change from one call
> to the next.  So there is no translation from the operator notation to
> bsxfun.  But I don't see this as a problem.  If you want your code to
> run in Matlab, then you have to use bsxfun when that is the operation
> you want.
>
> jwe

I know this may be stupid, but would it possible to deactivate the
auto bsx when we start a session of octave?
Something like
octave --nobsx

being auto-bsx the default (or even at .octaverc level).

I guess this can be an over-burden to the code. Just asking.


-- 
M. Sc. Juan Pablo Carbajal
-----
PhD Student
University of Zürich
http://ailab.ifi.uzh.ch/carbajal/