From bug-octave-request at che dot utexas dot edu  Tue May 31 20:03:19 1994
From: John Eaton <jwe at che dot utexas dot edu>
To: Frederick A Niles (Rick) <niles at axp745 dot gsfc dot nasa dot gov>
cc: bug-octave at che dot utexas dot edu
Date: Tue, 31 May 94 20:03:15 EDT

Frederick (Rick) A Niles <niles at axp745 dot gsfc dot nasa dot gov> wrote:

: 	     Desirable Matlab features missing in Octave.

: 1) octave_path like matlab_path for user defined *.m files. So they
:       don't all have to be in the current directory.

You can use the built-in variable LOADPATH for this.  It's described
and indexed in the manual.

:       Perhaps a ~/.octave file would be appropriate.

Octave already looks for the files ~/.octaverc and ./.octaverc in
addition to the system-wide /usr/local/lib/octave/VERSION/octaverc.
I don't think this is properly explained in the manual yet, but should
be for 1.1.

: 2) Optional parameters for functions. e.g.
: 	function out=tester(in, a)
: 	if(~exist('a')),a=1,end
: 	a
: 	out =1;

In this case, the variable a does exist because it is in the
function's symbol table.  Apparenly Matlab makes it appear as though
a function parameter doesn't exist if it is not given a value when the
function is called.  Perhaps this is reasonable, so I'll consider
fixing it to work like Matlab.

: 3) "load" of plain ASCII data files as one large array or group of vectors.
:       (I've written a .m file for this but it is extremely slow for
:        large (6 col, 5000 row) files.) This would fall under:
: 	  * Make load work for files saved by Matlab.

I'm not sure what file format you are asking for.  Octave can already
read a matrix stored as ASCII data, but you have to provide the size
and name of the variable in the header of the file.  Something like:

  # name: a
  # type: matrix
  # rows: 5000
  # columns: 2
   0.58778941631317139 0.88879448175430298
   0.81900960206985474 0.29288467764854431
   ...

Version 1.1 will have fread() and fwrite(), and may include support
for binary reading and writing of data files with load and save.

: 4) Why not alias 'whos' to 'who -l' for us Matlab users?

That seems reasonable.

: In addition, why can't one index arrays of characters, like C?
: 	a = "apple"
: 	then a(2) is --> 'p'

This simply hasn't been implemented yet.  It should be done for the
next release.

Thanks,

jwe