I figured it out a bit ago.. finally.. because I'm a dweeb..<br><br>I assumed buffer was a memory function :) It greatly confused me. I just started up with PostGIS a few weeks ago and am just now seeing the term buffer in all the programs I've been using for GIS visualization.
<br><br>Thanks for the description :)<br><br>Shane<br><br><div><span class="gmail_quote">On 9/18/07, <b class="gmail_sendername">Nico Mandery</b> <<a href="mailto:nicomandery@googlemail.com">nicomandery@googlemail.com</a>
> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi Shane,<br><br>sorry for the delay, i had no access to the Internet for while.
<br><br>here is a short definition of the term buffer from<br><a href="http://www.fws.gov/data/IMADS/glossary.htm">http://www.fws.gov/data/IMADS/glossary.htm</a> :<br><br>buffer - A zone of a specified distance around coverage features. Both
<br>constant- and variable-width buffers can be generated for a set of<br>coverage features based on each feature's attribute values. The<br>resulting buffer zones form polygons-areas that are either inside or<br>outside the specified buffer distance from each feature. Buffers are
<br>useful for proximity analysis (e.g., find all stream segments within<br>300 feet of a proposed logging area).<br><br>In this context you could create a buffer with a distance X and a<br>buffer with a distance Y around the point, and then look for point
<br>wicht are in the in the area of (bufferX-bufferY).<br><br>nico<br><br>>Could you reply with a URL to what buffers are and how they would be<br>>used in this context? I'm >totally unfamiliar.<br>><br>>
<br>> On 9/9/07, Nico Mandery < nicomandery <at> <a href="http://googlemail.com">googlemail.com</a>> wrote:<br>>> Hi Rainer,<br>>><br>>> You could could use a buffer instead of bounding boxes.
<br>>> Just an idea<br>>><br>>> Nico<br>>><br>>> Am Sonntag 09 September 2007 schrieb postgis <at> <a href="http://jochem.name">jochem.name</a>:<br>>> > Hi,<br>>> ><br>
>> > what I want to do is finding certain features in some distance around a<br>>> > certain point. Those features should be located in some corridor between X<br>>> > and Y km around this point. Currently I've solved this problem by
<br>>> > computing two bounding boxes of X and Y km around the point and taking the<br>>> > difference of those. So far so good.<br>>> ><br>>> > But I don't want to have some quadratic box but a real circle - is there
<br>>> > any way to achieve this?<br>>> ><br>>> > Best regards,<br>>> > Rainer<br>>> > _______________________________________________<br>>> > postgis-users mailing list
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