yuji.shirasaki at nao.ac.jp
Fri Sep 24 19:32:48 PDT 2004
> I would recommend that the Point function take three variables
> ra,dec, and size. So
> rather than
> where pos=Point(23,+30) and size=1.0 and format='fits'
> I would recommend
> where pos=Point(23,+30,1.0) and format='fits'
I also defined Circle and Box for expressing the region in the
sky coordinate. Point is used as an expression of a point in
the sky, so it does not have size and is a zero dimenstional value.
> This than asks if the image contains pixels within a particular circular
> region and this should
> be a single step. What would point(23,+30) or size=1.0 mean? Or size
> by itself?
Point(23,+30) means the position of (Ra,Dec)=(23.0 deg, +30 deg)
in the celestial coordinate ans size mean the box region size as
defined in SIAP.
I just used an example using column "pos" and "size" to show how
SIAP query can be directly translated to SQL. If "region" column
is defined in the table, one can specify the region by a single step
like this: "region = Box((23, +30), 1.0, 1.0)".
Yuji SHIRASAKI, Research Fellow +81-422-34-3579 (tel)
National Astronomical Observatory of Japan +81-422-34-3840 (fax)
Osawa, Mitaka, Tokyo, Japan yuji.shirasaki at nao.ac.jp
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