<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">I use a custom equal area projection for some large oceanic regions I work in, but depending on the extent of your linestrings, it is likely that the UTM projection for your part of the globe will give a reasonable result, if you are not too near the poles.<br><br>You may even find native lat/long gives an acceptabvle result, it all depends on how much precision you need for your purposes.<br><br>Given around 110,000m/degree, if you just want a small buffer around the linestring, and whether it is 5m or 15m doesn't matter, you could try buffering with your lat/long data & a distance of 0.0001 degrees, which should be around 10m, depending on your latitude.<br><br>--- On <b>Sat, 3/3/12, Ed Linde <i><edolinde@gmail.com></i></b> wrote:<br><blockquote style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; padding-left: 5px;"><br>From: Ed Linde
<edolinde@gmail.com><br>Subject: Re: [postgis-users] Forming a BAND around a linestring<br>To: pcreso@pcreso.com<br>Cc: "PostGIS Users Discussion" <postgis-users@postgis.refractions.net><br>Date: Saturday, March 3, 2012, 7:18 AM<br><br><div id="yiv1477371529">Thanks for the tip! Do you recommend a "suitable projection" for the buffer operation that will not produce distorted buffers?<br><br><div class="yiv1477371529gmail_quote">On Fri, Mar 2, 2012 at 7:15 PM, <span dir="ltr"><<a rel="nofollow" ymailto="mailto:pcreso@pcreso.com" target="_blank" href="/mc/compose?to=pcreso@pcreso.com">pcreso@pcreso.com</a>></span> wrote:<br>
<blockquote class="yiv1477371529gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><table border="0" cellpadding="0" cellspacing="0"><tbody><tr><td style="font:inherit;" valign="top">ST_Buffer(<linestring>, distance)<br>
<br><a rel="nofollow" target="_blank" href="http://www.postgis.org/docs/ST_Buffer.html">http://www.postgis.org/docs/ST_Buffer.html</a><br><br><br>Note that if your data is lat/long (such as EPSG:4326) with units in degrees, then you will get somewhat distorted buffer distances, and a better result by transforming your linestring to a more suitable projection for the buffer operation, then transform it back.<br>
<br>eg:<br><br>ST_Transform(ST_Buffer(ST_Transform(<linestring>, SRID), distance),4326)<br><br>HTH,<br><br> Brent Wood<br>--- On <b>Fri, 3/2/12, Ed Linde <i><<a rel="nofollow" ymailto="mailto:edolinde@gmail.com" target="_blank" href="/mc/compose?to=edolinde@gmail.com">edolinde@gmail.com</a>></i></b> wrote:<br>
<blockquote style="border-left:2px solid rgb(16,16,255);margin-left:5px;padding-left:5px;"><br>From: Ed Linde <<a rel="nofollow" ymailto="mailto:edolinde@gmail.com" target="_blank" href="/mc/compose?to=edolinde@gmail.com">edolinde@gmail.com</a>><br>Subject: [postgis-users] Forming a BAND around a linestring<br>
To: "PostGIS
Users Discussion" <<a rel="nofollow" ymailto="mailto:postgis-users@postgis.refractions.net" target="_blank" href="/mc/compose?to=postgis-users@postgis.refractions.net">postgis-users@postgis.refractions.net</a>><br>Date: Friday, March 2, 2012, 11:17 PM<div><div class="yiv1477371529h5"><br><br><div>Hi All,<div>
I have a set of points with (x,y) co-ordinates that belong to a single object ex: a segment in a road network.</div><div>If we made a LINESTRING that connected these points (x,y), then I would like to have a BAND or RANGE</div>
<div>around the linestring of say 10 meters wide that would probably make it look more like a polygon or some </div><div>area. How can I achieve this in postgis 2.0? Do I need to use some library like GDAL in order to achieve this?</div>
<div><br></div><div>Cheers,</div><div>Ed</div>
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