Changes between Initial Version and Version 1 of UsersWikiCreateFishnet


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Timestamp:
Nov 1, 2011, 1:49:26 PM (13 years ago)
Author:
Mike Taves
Comment:

add function

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  • UsersWikiCreateFishnet

    v1 v1  
     1= Create Fishnet Grid =
     2
     3Make a 2D grid of rectangular polygons, which is sometimes called a fishnet grid.
     4
     5Use the following source:
     6{{{
     7CREATE OR REPLACE FUNCTION ST_CreateFishnet(
     8        nrow integer, ncol integer,
     9        xsize float8, ysize float8,
     10        x0 float8 DEFAULT 0, y0 float8 DEFAULT 0)
     11    RETURNS SETOF geometry AS
     12$$
     13SELECT ST_Translate(cell, j * $3 + $5, i * $4 + $6)
     14FROM generate_series(0, $1 - 1) AS i,
     15     generate_series(0, $2 - 1) AS j,
     16(
     17SELECT ('POLYGON((0 0, 0 '||$4||', '||$3||' '||$4||', '||$3||' 0,0 0))')::geometry AS cell
     18) AS foo;
     19$$ LANGUAGE sql IMMUTABLE STRICT;
     20}}}
     21
     22Example:
     23{{{
     24SELECT ST_Collect(cells)
     25FROM ST_CreateFishnet(3,4,10,10) AS cells;
     26}}}
     27[[Image(http://i.stack.imgur.com/vQY0Z.png)]]