From maintainers-request at octave dot org Tue Sep 14 16:27:10 2004
Subject: Re: Cell arrays of strings in "sort" and "unique"
From: "John W. Eaton" <jwe at bevo dot che dot wisc dot edu>
To: David Bateman <David dot Bateman at motorola dot com>
Cc: maintainers at octave dot org, Keith Goodman <kwgoodman@gmail.com>
Date: Tue, 14 Sep 2004 17:26:15 -0400

On 14-Sep-2004, David Bateman <David dot Bateman at motorola dot com> wrote:

| I thought this was a bit crufty as a solution. However, given that the
| basic sorting code is written as a template it would be relatively
| painless to add sorting of cell arrays of strings as well. Should
| probably clean up sort.cc in any case since the NDArray, complexNDArray
| and charNDArray stuff might also be written as a template.

Yes, I noticed that there is now a lot of duplicated code in sort.cc.

| http://www.mathworks.com/access/helpdesk/help/techdoc/ref/sort.html
| 
| it seems that matlab has also added a "mode" flag that can define
| ascending or descending sorted order. Which again is relatively easy
| to add, but again more work :-(

The price of aiming at a moving target.

| However, if we are going to this level of compatiability, maybe we
| should also revisit the complex sorting code and the decision to do
| the sorting only on the absolute value rather than in a matlab
| compatiable way. Then again maybe not as sorting non ordinate values
| doesn't make much sense in any case.

We might as well be compatible if it is not too difficult.  In the old
days, I think they only said that complex elements X were sorted by
ABS(X), so I believe Octave was doing the compatible thing at some
point.  But now they say that matches are further sorted by ANGLE(X).
I would think that it should not be too hard to add that to the
complex comparison function.

jwe