Re: Data frames ?

[Pascal A. Dupuis]

On Mon, Oct 29, 2007 at 01:37:34PM -0400, John W. Eaton wrote:
> On 29-Oct-2007, David Bateman wrote:
> 

> I think that if you want to do this kind of thing, it would be best to
> just add property lists to variables.  Then property lists could hold
> arbitrary information, not just column (row?, Nth-dimension?) labels.
> It seems to me that these should apply to variables in the symbol
> table, or possibly the octave_value object, not the underlying Matrix
> or other data structures.
> 
> An immediate problem is that property lists could not be saved to MAT
> files, and we would have to modify Octave's own data file formats to
> save and load them.  That would cause some backward compatibility
> problems.
> 

I searched a bit onto the net and find this:
http://www.mathworks.com/matlabcentral/files/6657/matdat.zip

this is an implementation of dataframes using MatLab object
features. The code seems a bit odd (uses '&&', must be replaced by
'&') but does work. So, this is maybe to be on hold until octave3.1 ?

I also got a suggestion to use structure containing vectors, but then
the problem is that the struct is displayed component by components.

About backward compatibility, there will always be some concerns
introducing new features. 

Best regards

Pascal Dupuis