[postgis-users] Converting meters to another unit

[Paragon Corporation]

Richard,
 
Are you points in longitude, latitude.  If they are the best place to start
might be using the geography type.  This requires using PostGIS 1.5+
 
http://www.postgis.org/documentation/manual-1.5SVN/ch04.html#PostGIS_Geograp
hy
 
You can also read the free chapter of our book which covers this in some
detail.
 
http://www.postgis.us/chapter_01
 
Leo
http://www.postgis.us
 

  _____  

From: postgis-users-bounces at postgis.refractions.net
[mailto:postgis-users-bounces at postgis.refractions.net] On Behalf Of Richard
Gomes
Sent: Monday, April 04, 2011 12:46 AM
To: postgis-users at postgis.refractions.net
Subject: [postgis-users] Converting meters to another unit


Hi All,

I'm a newbie on PostGIS and GIS in general.

Reading section "Taking Advantages of Indexes" at
    http://postgis.refractions.net/docs/ch04.html#id2638955

... I became confused regarding how I could retrieve points which are
distant up to 500 meters from a given point.
The question is actually how I can transform 500 meters onto some some other
figure on a unit I don't understand very well what it is about. I need this
calculation in order to determine a Box3d like the article suggests.

Thanks a lot and regards,

-- 

Richard Gomes


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