A 'superset' data format

Mike Dallwitz md at ENTO.CSIRO.AU
Wed Jul 26 13:54:52 CEST 2000

> From: Stan Blum <sblum at CALACADEMY.ORG>

> There is a STRONG reason for moving a data set between the various
> applications that deal with descriptive data: a single person might want
> to use DELTA, LucID, PAUP and McClade in the same study. It would be
> "nice" to have the capability to create and maintain a single data set
> that could store and "serve" data to each application.

This is the raison d'etre of DELTA. To quote from the Introduction in the
User's Guide:

   When taxonomic descriptions are prepared for input to computer programs,
   the form of the coding is usually dictated by the requirements of a
   particular program or set of programs. This restricts the type of data
   that can be represented, and the number of other programs that can use
   the data. ... The DELTA (DEscription Language for TAxonomy) system was
   developed to overcome these problems. ... A format-conversion program,
   Confor, converts DELTA-format data into natural language, or into formats
   required by several other programs, including Key (generation of keys),
   Dist (generation of distance matrices), Paup, MacClade (Nexus), and
   Hennig86 (cladistic analysis), and Intkey (interactive identification and
   information retrieval).

In other words, DELTA was designed to be a single source for the descriptive
data required by a variety of applications. It still fulfils this function
better than other formats currently in use - see

> If we could create the specification for that data set, I would judge this
> effort a success.

Producing such a specification, i.e. for a new 'superset' data format, was
one of the goals mentioned in the minutes of the last meeting of the
TDWG-SDD group. I agree with Stan that it is the most important goal, and
perhaps the discussion should start to focus more on it. Also, more progress
might be made if the initial effort were directed to the less controversial
and more achievable parts - perhaps a discussion and consolidation of the
features used by existing programs. The above-mentioned document might be a
starting point.


Mike Dallwitz

CSIRO Entomology, GPO Box 1700, Canberra ACT 2601, Australia
Phone: +61 2 6246 4075   Fax: +61 2 6246 4000
Email: md at ento.csiro.au  Internet: biodiversity.uno.edu/delta/

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