Andreas, ST_SetSRID requires an SRID as the second argument. e.g. ST_SetSRID(geom, 4326) I'm assuming that is what you are missing. Leo http://www.postgis.us
_____ From: postgis-users-boun...@postgis.refractions.net [mailto:postgis-users-boun...@postgis.refractions.net] On Behalf Of Andreas Forø Tollefsen Sent: Friday, August 20, 2010 5:22 PM To: postgis-users@postgis.refractions.net Subject: [postgis-users] Vector Grid / Fishnet - ST_MakeEnvelope Hi all. I am currently developing a global vector grid from a set of centroid points. My data includes a csv file defining the x and y coordinate of each point. These points are imported into a table. I then add a point geometry field and apply the ST_MakePoint function to create the point features. All well. However, the next step is to create a bounding box for each of the points. In other words, I want a vector cell of 0.5 decimal degrees surrounding each point. I have tried using the ST_MakeEnvelope function as this allows me to use the x and y coordinate, and subtract and add 0.25 to the centroid x and y value. However, I have not been able to use the ST_MakeEnvelope as i receive an error. I cannot figure out what i am doing wrong. I have attached my sql below. Thanks for any help i might get. -- CREATE TABLE points( -- id int, -- xcoord float, -- ycoord float) -- COPY points(ID,XCOORD,YCOORD) -- FROM 'c:/postgis/pgpt.csv/pgpt.csv' -- WITH DELIMITER AS ',' -- CSV HEADER; -- -- ALTER TABLE points ADD PRIMARY KEY (id) -- SELECT AddGeometryColumn('public', 'points', 'centroid', 4326, 'POINT', 2); -- -- UPDATE points SET centroid=ST_SetSRID(ST_MakePoint(xcoord, ycoord), 4326); -- -- SELECT AddGeometryColumn('public', 'points', 'cell', 4326, 'POLYGON', 2); -- -- UPDATE points SET cell=ST_SetSRID(ST_MakeEnvelope(xcoord-0.25,ycoord-0.25,xcoord+0.25,ycoord+0 .25, 4326)); -- This last line give me: ERROR: function st_setsrid(geometry) does not exist LINE 20: UPDATE points SET cell=ST_SetSRID(ST_MakeEnvelope(xcoord-0.2... ^ HINT: No function matches the given name and argument types. You might need to add explicit type casts. ********** Error ********** ERROR: function st_setsrid(geometry) does not exist SQL state: 42883 Hint: No function matches the given name and argument types. You might need to add explicit type casts. Character: 501
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