If I understood correctly you always save the output to a file using the function org-babel-octave-wrapper-method, right? Maybe instead of using "%s save -ascii %s ans" to save the information to a file you can use "%s save -text %s ans" I tested this for numbers, strings and matrices and it seems to do the right thing. However, octaves adds some comment lines in the beginning of the file that you will probably need to remove, but you just need to remove lines that start with "#".

Regarding which value is returned, maybe you can use the same approach employed for python, where a line "return variable" is required in the end of the block, instead of just returning the value of ans.

In fact, I don't like to put a return statement in the end of the block just to make babel happy (python included), since I don't want this when I tangle the file, but this is the most flexible way.

Maybe a good feature request for babel it that instead "exports: value" one has to write "exports: value variable" and this would have the effect of the "return variable" in the end of the block that we have right now for python.

Regarding the graphical output, It is probably better to use :results file as suggested in the TODO. There may be necessary a lot of details in the graphic output such as labels, setting axis, etc.. It is better to let the user handle this in the code and just put the link to the file.

• State "DONE" from "TODO" 2010-05-21 Fri 20:43
• State "TODO" from "" 2010-04-30 Fri 17:00

Current solution is imperfect: it involves the matlab process signaling completion by removing a lock file rather than using the canonical org-babel comint completion functions.

• State "TODO" from "" 2010-03-18 Thu 12:37

Strings were being returned as their ascii codes.

We have adopted Darlan's suggestion of using save -text %s ans (and delting the comment lines), which seems to provide a solution.

'octave string'

'string from matlab'

• State "TODO" from "" [2010-03-17 Wed 23:3

Currently we are like pyuthon and ruby in that we can use :results file and the block will output a link to that file, but unless your code takes care of it (e.g. write graphics to file), no content will be written to that file.

However, would it be appropriate to move to the org-babel-R model, whereby if :results file is supplied, any graphical is automatically diverted to that file?

In order to get graphical output without leaving open graph windows during evaluation, the following can be used:

#+begin_src octave :output file :file chart.png
figure( 1, "visible" , "off" );
sombrero;
print -dpng chart.png
#+end_src

The figure command opens an invisible graph window where the next plot commands should act.

Then, the print command exports the graph to a file.

• State "TODO" from "" 2010-03-18 Thu 13:57

In :results value mode, we return whatever value the variable 'ans' has at the end of the block. However, there are some problems with this as can be seen from the following session:

octave> 'hello'
ans = hello
octave> ans
ans = hello
octave> x = 19
x =  19
octave> x
x =  19
octave> ans
ans = hello

So although this works as expected:

z + 0

This doesn't

z

As part of its internal operation, org-babel appends a special end-of-output string at the end of each block and it is this string's value (integer ascii codes) that is being returned here.

Of course, this works

ans

• State "TODO" from "" 2010-03-16 Tue 22:12

• State "TODO" from "" 2010-03-18 Thu 01:27
• -nodisplay ?
• -nojvm ?

• State "TODO" from "" 2010-03-18 Thu 01:10

• State "TODO" from "" 2010-03-18 Thu 01:09

-nosplash doesn't seem to do the trick.

• State "TODO" from "" 2010-03-18 Thu 01:29

At the moment I'm using a massive hack: insert

(cd "/ddavison@tombstone.princeton.edu:") ;; DED

around line 4253 in matlab.el so that my matlab sessions run on a machine with matlab installed.