From: Paul Ramsey <pramsey@cleverelephant.ca>
Date: Thu, 3 Jun 2004 04:51:26 +0000 (+0000)
Subject: Document the expand() function (finally!)
X-Git-Tag: pgis_0_9_1~226
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=8c574d0eb713c9d50ec3b6000c0414feba552acd;p=postgis

Document the expand() function (finally!)


git-svn-id: http://svn.osgeo.org/postgis/trunk@568 b70326c6-7e19-0410-871a-916f4a2858ee
---

diff --git a/doc/postgis.xml b/doc/postgis.xml
index 109c32aa3..3e3390d9a 100644
--- a/doc/postgis.xml
+++ b/doc/postgis.xml
@@ -2491,6 +2491,16 @@ is simple (does not pass through the same point more than once).
 						</para> 
 					</listitem> 
 				</varlistentry> 
+				<varlistentry> 
+					<term>expand(geometry, float)</term> 
+					<listitem> 
+						<para>This function returns a bounding box expanded in all directions
+						from the bounding box of the input geometry, by an amount specified
+						in the second argument.  Very useful for distance() queries, to add
+						an index filter to the query.
+						</para> 
+					</listitem> 
+				</varlistentry> 
 				<varlistentry> 
 					<term>collect(geometry set)</term> 
 					<listitem>