2009/7/15 Peter W. Draper <[log in to unmask]>:
> On Wed, 15 Jul 2009, Mark Taylor wrote:
>
>> On Wed, 15 Jul 2009, Peter W. Draper wrote:
>>
>> > On Tue, 14 Jul 2009, Tim Jenness wrote:
>> >
>> > > On Wed, 15 Jul 2009, Peter W. Draper wrote:
>> > >
>> > > > I also suspect that the elephant in the room against 1D FITS is
>> > > > handling the WCS information. That's considerably simplified using
>> > > > a table.
>> > > >
>> > >
>> > > but AST handles it no problem :-;
>> > >
>> > > So it's been decided that everything is a LutMap?
>> >
>> > Yes. For now anyway. No doubt given time this will get back to where we
>> > were (requires STC they'll say).
>>
>> Maybe. But unlike for 2+ dimensional arrays I don't really see what's
>> so great about using WCS rather than a LUT for 1d. And if you can avoid
>> reading the FITS paper and writing the software to make sense of it,
>> that's good news (AST's "no problem" presumably covers several years of
>> David's blood sweat and tears). Using WCS presumably saves you a factor
>> of ~2 in file size - does it have other major benefits?
>
> The main benefit was following a well thought out existing standard which
> has most of the things in the WCS area already sorted. The problem, which
> I'm happy to agree with, is that the data model is quite restrictive,
By which I presume you mean "the FITS-WCS data model"? We're probably
all agreed then on that. That's one of the things I said in my AST
presentation at the Cambridge interop before the demise of Starlink.
But there are better ways of generalising than to go to a simple
table.
David
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