[postgis-users] ST_MapAlgebraExpr() Function

[Deepak R aj Awasthi]

Hello,


I am a M.Sc. student and currently working with postgreSQL/PostGIS to handle  raster.  I have installed PostgreSQl  9.0 and PostGIS 2.0 in  windows 7  home premium OS. I had no problem on handling raster so far but now I got problem while accessing ST_MapAlgebraExpr () function  which takes two rasters as function arguments. I have followed the example provided in the link below as follows.

First, I create the table as given,

CREATE TABLE fun_shapes(rid serial PRIMARY KEY, fun_name text, rast raster);Then, the second syntax to insert raster and finally the use of the function ST_MapAlgebraExpr()  as.
SELECT  ST_MapAlgebraExpr( area.rast, bub.rast, 'rast2', '8BUI', 'INTERSECTION', 'rast2', 'rast1') As interrast, ST_MapAlgebraExpr( area.rast, bub.rast, 'rast2', '8BUI', 'UNION', 'rast2', 'rast1') As unionrast
FROM  (SELECT rast FROM fun_shapes WHERE fun_name = 'area') As area
CROSS JOIN  (SELECT rast 
FROM fun_shapes WHERE fun_name = 'rand bubbles') As bub
 

 http://postgis.refractions.net/documentation/manual-svn/RT_ST_MapAlgebraExpr2.html


But I got error on using this syntax as:

ERROR:  function st_mapalgebraexpr(raster, raster, unknown, unknown,  unknown, unknown, unknown) does not exist
 LINE 58: SELECT  ST_MapAlgebraExpr()
  HINT:  No function matches the given name and argument types. You might need to add explicit type casts.


 Although I am new to this database, I think that there is problem with  PostGIS 2.0 to support the function. If this the case which version I have  to install to use this function. Can anyone provide me solution for it.

 Thanks

 With Best Regards,
 Deepak
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20120122/21e0aa70/attachment.html>