do something useful and simple first
roy at cacr.caltech.edu
Fri Feb 6 09:53:09 PST 2009
Yes, OpenSkyQuery is excellent for crossmatch. However, I maintain that
what you can do there can be done easily as a two-stage process: first
do multicone for the rough crossmatch, then download the result to the
desktop and refine the result with further selections, using
Topcat/Stilts. So multicone gives us the ability to do crossmatch, and
of course we can do single-catalog query with existing facilities (eg
Vizier). What else is there? What are the "many capabilities" you
There are already many versions of multicone out there (*). It is mainly
a rather simple question of standard formatting for the upload table
(RA,Dec,ID,radius for each). The version 2 standard could handle
asynchronous operation for vary large queries.
Am I alone in this addiction to customer requirements and pragmatism? Am
I just being very short-sighted? Everyone else in this list is sure we
need the generality, complexity, and sophistication that TAP may provide
Ray Plante wrote:
> Hi Roy,
> On Fri, 6 Feb 2009, Roy Williams wrote:
>> and doesn't give our customers anything that they will value.
> I think this mischaracterizes the TAP effort. We have seen from our
> own summer schools that OpenSkyQuery is clearly near or at the top of
> the list of things people find most valueable. TAP is intended to be
> a better OpenSkyNode.
> It is also intended to be a better cone search, able to do
> multi-cones. More to the point, TAP is meant to be a general
> foundation that many capabilities can be built upon. This is
> understandably harder to do than a simple cone search or a simple
> multi-cone search.
> Now, it's understandable that you might not want to wait around for
> TAP to settle to get a multi-cone capability. And you can argue that
> it's more productive to start simple, which is why we have cone
> search. But we've also demonstrated that, unless you are really lucky
> or really smart, it's hard to go from simple to general without a
> major rewrite.
> I might suggest that if you would like to see a simple multi-cone,
> perhaps building on the current cone search, that you draw up a proposal.
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