<p dir="ltr">Thanks Oleg for the help.<br>
I am looking at the examples of the spgist opclasses, and would get back to you in case of any doubt.<br>
My idea for clustering was to index point data using quad trees and display a single point in place of cluster of spatially close points.<br>
The zoom level will decide the spatially close points that can be represented as a single point. This zoom level would be given by the map(user). If this value is integrated in indexing, the nodes having the zoom value lower than the asked value would be send by the dB to the map. <br>
The purpose of keeping the child nodes was to show the number of points in the cluster represented by the single point. This point will be that node whose zoom value equaling the zoom value of the map.<br>
I know this will make index creation very slow, but once done, the point display in the map might become a lot cleaner. <br>
This was what I thought on implementation of the work.<br>
Your feedback and suggestions are much needed.</p>
<p dir="ltr">Regards, <br>
Mohit</p>
<div class="gmail_quote">On Jun 6, 2014 4:45 PM, "Oleg Bartunov" <<a href="mailto:obartunov@gmail.com">obartunov@gmail.com</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr"><div><div>Mohit,<br><br></div>could you explain us what do you want from us :)<br></div><div>Basically, you need to create new type (if needed) and write opclass for spgist. There are several questions:<br>
</div><div><br>1. Where do you get zoom level ?<br></div><div>2. Are you sure you want to keep number of child nodes ? It's too slow for index creation.<br></div><div><br></div><div>you may look examples of spgist opclasses <br>
src/backend/access/spgist<br><br> Oleg<br></div><div><div><div><div>
<div class="gmail_quote">On Jun 5, 2014 12:50 PM, "mohit kumar" <<a href="mailto:mohitkharb@gmail.com" target="_blank">mohitkharb@gmail.com</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="ltr"><div><div><div><div>Thanks Strk for the help.<br></div>I have now moved to postgresSQL implementation of the sp-gist indexing and am working on it. <br></div><br>Hi Teodor,Oleg, actually along with the sp-gist index in PostGIS Geometry (point data) I wanted to store the zoom levels and number of child nodes along the indexes for a better indexing at a given zoom level.<br>
<br></div>Regards,<br></div>Mohit<br></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, Jun 4, 2014 at 3:00 PM, Sandro Santilli <span dir="ltr"><<a href="mailto:strk@keybit.net" target="_blank">strk@keybit.net</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">[moved exclusively to postgis-devel]<br>
<div><br>
On Wed, Jun 04, 2014 at 12:29:56AM +0530, mohit kumar wrote:<br>
> On Tue, Jun 3, 2014 at 5:20 PM, Sandro Santilli <<a href="mailto:strk@cartodb.com" target="_blank">strk@cartodb.com</a>> wrote:<br>
<br>
</div><div>> > What's in that package that isn't already in the PostgreSQL<br>
> > SP-GiST index ?<br>
> > <a href="http://www.postgresql.org/docs/9.2/static/spgist.html" target="_blank">http://www.postgresql.org/docs/9.2/static/spgist.html</a><br>
> ><br>
> > I mean, don't you only need to implement the PostGIS connector ?<br>
><br>
> I wanted to modify the code for sp-gist to inculcate another integer field<br>
> for various levels of clustering, so worked on the source code by purdue<br>
> research group.<br>
<br>
</div>The best would be to contribute a patch back to PostgreSQL to make the<br>
existing sp-gist code capable of doing what you need, if it isn't already.<br>
<br>
I've added Teodor and Oleg (authors of the PostgreSQL implmentation) in Cc,<br>
could you describe what your additional integer is meant to provide ?<br>
<br>
Teodor, Oleg, the context here is adding sp-gist support to PostGIS Geometry<br>
and using those indices to quickly compute population in a quadtree tile.<br>
<br>
REF:<br>
<a href="http://www.google-melange.com/gsoc/proposal/public/google/gsoc2014/mohitkharb/5698390809640960" target="_blank">http://www.google-melange.com/gsoc/proposal/public/google/gsoc2014/mohitkharb/5698390809640960</a><br>
<br>
--strk;<br>
<br>
() ASCII ribbon campaign -- Keep it simple !<br>
/\ <a href="http://strk.keybit.net/rants/ascii_mails.txt" target="_blank">http://strk.keybit.net/rants/ascii_mails.txt</a><br>
</blockquote></div><br><br clear="all"><br>-- <br><div><div>Mohit Kumar<div>+91-970-3840-175<div>Lab For Spatial Informatics<br>International Institute of Information Technology<br>Hyderabad, India</div></div></div></div>
</div>
</blockquote></div>
</div></div></div></div></div>
</blockquote></div>