Re: How to get Octave.app to work?

[Vic Norton]

On Sep 3, 2007, at 1:34 PM, Matthias Brennwald wrote:

> > Test 1. From terminal I execute
> >     vic$ /Applications/Octave.app/Contents/Resources/bin/octave
> > This gets me into octave-2.9.13. Now I execute
> >     octave-2.9.13> printf("%d\n", fopen ("~/desktop/
> > octave_output.txt", "wt"));
> > The output is
> >     3
>
> You've just opened the file with write access...

That's what I want to do, write to it.

> > Test 2. From terminal I execute
> >     vic$ /usr/local/bin/octave
> > This gets me into octave-2.9.9. Now I execute
> >     octave> printf("%d\n", fopen ("~/desktop/octave_output.txt",
> > "wt"));
> > The output is
> >     -1
>
> ...and you're trying to open the same file with write access again. I
> guess that might explain why this second call to fopen is not
> successful. Not sure, though.

This is a different shell and a different version of octave,  
Matthias. The -1 output tells me that I can't write to the  
octave_output.txt file on my desktop because this octave (2.9.9)  
can't see it.

Why it can't see the file is what perplexes me. Every week I have  
octave-2.2.9 write files from within a perl script. The relevant perl  
line is
   `octave "$maindir/Octave/m/$octavescript"`;
The octave script does some computations and writes a comma-separated- 
value (.csv) file. The version of octave used resides in /usr/local/ 
bin/octave. This is the octave-2.9.9 of Test 2 above.

Inside the octave script ($octavescript) the code looks like this
   file = [ "Output/spdrPortf39T_", deblank(base(baseIdx, :)),  
wgtSys, "_26"];
   file = [ file, ".csv" ];
   fid = fopen (file, "wt");
   fprintf (fid, "Historical Sharpe-Optimal SPDR Portfolios (based  
on 39 weeks of 13-week returns)\n");
   ...
Since the script always works, the file id, fid, must be some  
positive integer. Why the file id is -1 in Test 2 is what perplexes me.


Regards,

Vic