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Re: IDL 5.2 array definition question.



Craig Markwardt wrote:
> 
> Paul van Delst <pvandelst@ncep.noaa.gov> writes:
> 
> > Hi,
> >
> > I'm sure this is a another hoary old chestnut of a question but here
> > goes....
> >
> > I have an IDL routine that returns the atomic weight of a requested
> > element - defined by symbol, name, or atomic number. I check the
> > validity of all these. Can somebody tell me why - in IDL 5.2 - my array
> > containing the valid symbol names has to be defined like:
> ...
> 
> Short answer: the IDL parser had a limit on the number of array
> elements that could be specified explicitly.  The number was 129 I
> believe.  It may be that this restriction was relaxed in IDL 5.3.

The documentation (that I read before posting the original message)
actually specifies this except the number that they guarenteed across
versions was only 25!. My (badly formed) question can be rephrased as:

why?

Like I alluded to previously, IDL 5.3 raised the limit to 65536 (or
thereabouts) which is way larger than any array initialisation anyone
would want to type by hand, but I would still like to know what design
decisions the pre-5.3 behaviour was based on. That's all.

paulv

-- 
Paul van Delst           Ph:  (301) 763-8000 x7274
CIMSS @ NOAA/NCEP        Fax: (301) 763-8545
Rm.202, 5200 Auth Rd.    Email: pvandelst@ncep.noaa.gov
Camp Springs MD 20746