re: Postal Codes and polygons. I've heard of basic techniques that use Commerce
Department (or was it Census within Commerce??) that give the basic points, but
the real run is deciding what the "center" of that polygon is. There is likely
a commercial solution available, and certainly you can buy a spreadsheet with
the zipcodes and their guestimated center. Fun project!
> Subject: Re: Spatial Search on Postal Code
> To: solr-user@lucene.apache.org
> From: emir.arnauto...@sematext.com
> Date: Fri, 4 Mar 2016 21:18:10 +0100
>
> Hi Manohar,
> I don't think there is such functionality in Solr - you need to do it on
> client side:
> 1. find some postal code polygons (you can use open street map -
> http://wiki.openstreetmap.org/wiki/Key:postal_code)
> 2. create zip to polygon lookup
> 3. create code that will expand zip code polygon by some distance (you
> can use JTS buffer api)
>
> On query time you get zip code and distance:
> 1. find polygon for zip
> 2. expand polygon
> 3. send resulting polygon to Solr and use Intersects function to filter
> results
>
> Regards,
> Emir
>
> On 04.03.2016 19:49, Manohar Sripada wrote:
> > Thanks Emir,
> >
> > Obviously #2 approach is much better. I know its not straight forward. But,
> > is it really acheivable in Solr? Like building a polygon for a postal code.
> > If so, can you throw some light how to do?
> >
> > Thanks,
> > Manohar
> >
> > On Friday, March 4, 2016, Emir Arnautovic
> > wrote:
> >
> >> Hi Manohar,
> >> This depends on your requirements/usecase. If postal code is interpreted
> >> as point than it is expected to have radius that is significantly larger
> >> than postal code diameter. In such case you can go with first approach. In
> >> order to avoid missing results from postal code in case of small search
> >> radius and large postal code, you can reverse geocode records and store
> >> postal code with each document.
> >> If you need to handle distance from postal code precisely - distance from
> >> its border, you have to get postal code polygon, expand it by search
> >> distance and use resulting polygon to find matches.
> >>
> >> HTH,
> >> Emir
> >>
> >> On 04.03.2016 13:09, Manohar Sripada wrote:
> >>
> >>> Here's my requirement - User enters postal code and provides the radius.
> >>> I
> >>> need to find the records with in the radius from the provided postal code.
> >>>
> >>> There are few ways I thought through after going through the "Spatial
> >>> Search" Solr wiki
> >>>
> >>> 1. As Latitude and Longitude positions are required for spatial search.
> >>> Get
> >>> Latitude Longitude position (may be using GeoCoding API) of a postal code
> >>> and use "LatLonType" field type and query accordingly. As the GeoCoding
> >>> API
> >>> returns one point and if the postal code area is too big, then I may end
> >>> up
> >>> not getting any results (apart from the records from the same postal code)
> >>> if the radius provided is small.
> >>>
> >>> 2. Get the latitude longitude points of the postal code which forms a
> >>> border (not sure yet on how to get) and build a polygon (using RPT). While
> >>> querying use this polygon and provide the distance. Can this be achieved?
> >>> Or Am I ruminating too much? :(
> >>>
> >>> Appreciate any help on this.
> >>>
> >>> Thanks
> >>>
> >>>
> >> --
> >> Monitoring * Alerting * Anomaly Detection * Centralized Log Management
> >> Solr & Elasticsearch Support * http://sematext.com/
> >>
> >>
>
> --
> Monitoring * Alerting * Anomaly Detection * Centralized Log Management
> Solr & Elasticsearch Support * http://sematext.com/
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