[postgis-users] ST_Slope

[Pierre Racine]

> Does SELECT ST_AsBinary((gv).geom), (gv).val FROM (SELECT
> ST_DumpAsPolygons(ST_Slope(rast) gv FROM height_newcastle) foo calculate
> the slope surface from height_newcastle and then display it in OpenJump?

Yes...

> Do I not need to use '([rast.x] - 1) * 10 + [rast.y]') to assign the unique values
> anymore?

ST_MapAlgebraExpr(ST_AddBand(ST_MakeEmptyRaster(10, 10, 0, 0, 0.1, 0.1, 0, 0, 4269), '8BUI'::text, 1, 0), '32BUI',  '([rast.x] - 1) * 10 + [rast.y]'), 1, '8BUI'::text)

was just a test raster.

Pierre