pgSphere

[Chris Albertson <chrisalbertson90278@yahoo.com>]

I hate to cross post messages but some of you may want to
try this out.  I've been playing with this for a while. (I
get to mess with this kind of stuff at work.)  and pgSphere
could save someone working on an astronomical database some
serious time and effort while eliminating approximate solutions.

Amoung other problems pgSphere will allow one to querry for
(say) "All stars within X arcseconds of a given star. The
search will be fast, with no end to end linear searches or
approimatly correct pseudo-square bounding boxes.

Or more powerfully it will allow two datasets to be joined
by location. This is equivalent to asking "give me everything
in the TASS databs that is within X arcsecond of a star in
this other catalog.  This type of search typically eats up a
lot of time if programmed in Perl or C but can be very, very
fast using pgSphere.  Not only fast in terms of execution
time but in "programming time" too as it only time one SQL
stament to compute the catalog cross reference.



--- Janko Richter <jankorichter@yahoo.de> wrote:
> Date: Tue, 13 Jul 2004 22:40:01 +0200
> From: Janko Richter <jankorichter@yahoo.de>
> To: pgsql-announce@postgresql.org
> Subject: [Pgsphere-dev] pgSphere 1.0 beta1 released
> 
> The pgSphere development team is pleased to announce the first beta 
> release of
> the module pgSphere.  pgSphere adds data types to PostgreSQL which
> support
> spherical geometry.  The purpose of pgSphere is to provide uniform
> access to
> spherical data.
> 
> pgSphere provides the following functionality:
> 
> - input and output of spherical data in several formats (radians, 
> degrees, etc)  
> - containing, overlapping and other geometrical operations for
> different 
> objects
>   on a sphere.
> - various input and converting functions and operators
> - calculations of circumference and area of an object on a sphere
> - spherical transformations
> - indexed data access methods for spherical data types.
> 
> The following data types are supported:
> points, circles, lines, ellipses, coordinate ranges (box), polygons
> and 
> paths.
> 
> A variety of operators are implemented, including equality, contains,
> 
> overlaps,
> distance, circumference, center, etc...
> 
> A number of functions add support for area, components of
> coordinates,
> transformations, and many more.
> 
> Indexing is supported on all data type listed above using GiST and is
> 
> used with
> the following operators: contains, overlaps, crosses and equal/not
> equal.   
> Clustering is also supported using B-tree indexes for optimization
> purposes.
> 
> We want to release version 1.0 as soon as possible, hence testers are
> 
> welcome!
> 
> pgSphere development home page :
>   http://gborg.postgresql.org/project/pgsphere/projdisplay.php
> 
> Additional informations :
>   http://www.pgastro.org/cgi-bin/wiki.pl?pgSphere
> 
> Janko Richter
> 
> _______________________________________________
> Pgsphere-dev mailing list
> Pgsphere-dev@gborg.postgresql.org
> http://gborg.postgresql.org/mailman/listinfo/pgsphere-dev
> 


=====
Chris Albertson
  Home:   310-376-1029  chrisalbertson90278@yahoo.com
  Cell:   310-990-7550
  Office: 310-336-5189  Christopher.J.Albertson@aero.org
  KG6OMK


	
		
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