Re: ~/.octaverc overwrites OCTAVE_PATH!!

[Rosen Diankov]

I agree with you. the current savepath does break some things about
the flow of paths in octave. We recently started using octave for a
robotics framework ROS
(http://pr.willowgarage.com/wiki/rosoct#preview) and we are starting
to create many packages that optionally have octave code that use a
core ROS 'octave library'. In order for those functions to be visible
in octave, they have to be added to the path, so I would like the
users to be able to add a simple

export OCTAVE_PATH=...

in their .bashrc that automatically finds the correct directory and
includes it. The path will be dependent on the particular directory
their checkout tree lies in (which can change).

The problem with savepath is that it sucks in the current paths into
its one 'path' call, which makes using multiple build trees of the
robotics framework very hard.

According to the matlab savepath, there is a separate 'userpath'
variable that gets combined with the current paths.

Ideally, savepath would remove all directories in OCTAVE_PATH before
making the addpath call (there's no reason it should be calling path).

thanks,
rosen,

2008/12/22 Ben Abbott <address@hidden>:
>
> On Dec 22, 2008, at 1:37 PM, Rosen Diankov wrote:
>>
>> 2008/12/21 Ben Abbott <address@hidden>:
>>>
>>> On Dec 21, 2008, at 3:38 PM, Rosen Diankov wrote:
>>>
>>>> Hi all,
>>>>
>>>> I'm trying to append my own directory with octave files
>>>> (/usr/local/myoctavefiles) to the automatically set octave paths. At
>>>> first, I tried doing
>>>>
>>>> export OCTAVE_PATH=/usr/local/myoctavefiles
>>>>
>>>> but it didn't work since the auto-generated ~/.octaverc file (from
>>>> savepath) overwrites any added paths via the path function. Ie, the
>>>> ~/.octaverc file looks like:
>>>>
>>>> ## Begin savepath auto-created section, do not edit
>>>> path ('/usr/local/share/...',...)
>>>> ## End savepath auto-created section
>>>>
>>>> So the next obvious thing to do was to call
>>>> addpath('/usr/local/myoctavefiles') right after the '## End savepath
>>>> ...', but this has a very dangerous side-effect. The problem is that
>>>> the next time the user calls 'savepath', it will put
>>>> /usr/local/myoctavefiles inside the auto-generated code. And even if I
>>>> remove my addpath or set OCTAVE_PATH to something different, my path
>>>> will remain added to the octave path!
>>>>
>>>> So I propose a small savepath change that always puts
>>>> getenv('OCTAVE_PATH') inside the auto-generated code.
>>>> It would be great if this makes it into octave 3.0.4
>>>>
>>>> thank you,
>>>> rosen diankov
>>>
>>> If I understand you correctly you'd like to be able to dynamically add a
>>> specific path when octave is run. Have you looked at the command line
>>> options. For example,
>>>
>>>      octave --path "/usr/local/myoctavefiles"
>>>
>>> Other command line options are detailed at the link below.
>>>
>>>
>>>
>>> http://www.gnu.org/software/octave/doc/interpreter/Command-Line-Options.html#Command-Line-Options
>>>
>>> Ben
>
>>
>> It doesn't work, the ~/.octaverc file overwrites any paths from
>> OCTAVE_PATH, -p, or --path because savepath directly calls path. it
>> would be great if at least it called addpath.
>>
>> rosen,
>
> Do you mean you'd like to have the lines added to .octaverc by savepath use
> "addpath(...)" rather than "path(...)"?
>
> sigh ... I find the savepath command more trouble that it is worth :-(
>
> You may find the best solution it to modify .octaverc by manually and use
> addpath() to include your local octave directories.
>
> In any event, we will want to be compatible with matlab. Does matlab provide
> the functionality you're looking for?
>
> Ben
>
>
>