Changes between Initial Version and Version 1 of UsersWikiplpgsqlfunctionsDistance

Timestamp:

09/29/09 21:16:52 (15 years ago)

Author:

robe

Comment:

--

UsersWikiplpgsqlfunctionsDistance

@@ +1 @@
+
+{{{
+--
+-- ST_DWithin_Sphere(lonlat-point, lonlat-point, radius-in-meters) returns boolean
+--
+-- Meters/Degree @ 60N: select 1/distance_sphere('POINT(0
+60)','POINT(1 60)') = 1.79866403673916e-05
+--
+CREATE OR REPLACE FUNCTION ST_DWithin_Sphere(geometry, geometry, float8)
+        RETURNS boolean
+        AS 'SELECT $1 && ST_Expand($2,$3 * 1.79866403673916e-05) AND
+$2 && ST_Expand($1,$3 * 1.79866403673916e-05) AND ST_Distance_Sphere($1, $2) < $3'
+        LANGUAGE 'SQL' IMMUTABLE;
+
+
+}}}