[postgis-devel] [PostGIS] #1119: [raster] Modify ST_Mapalgebra so that the expression can refer to any band

[PostGIS]

#1119: [raster] Modify ST_Mapalgebra so that the expression can refer to any band
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 Reporter:  pracine         |       Owner:  pracine              
     Type:  enhancement     |      Status:  new                  
 Priority:  low             |   Milestone:  PostGIS Raster Future
Component:  postgis raster  |     Version:  trunk                
 Keywords:                  |  
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Description changed by pracine:

Old description:

> This could be useful for:
>
> -Writing expressions (like 'average') involving any band of the raster
>
> -Refer to weighted information created by ST_AsRaster() (the length or
> the area of the geometry intersecting with the pixel

New description:

 This could be useful for:

 -Writing expressions (like 'average') involving any band of the raster

 -Refer to weighted information created by ST_AsRaster() (the length or the
 area of the geometry intersecting with the pixel

 In the one raster version of MapAlgebra one could refer to the second band
 like this: 'rast[2]'.

 In the two rasters version of MapAlgebra one could refer to the second
 band like this: 'rast1[2] + rast2[2]'.

 'rast', 'rast1' and 'rast2' should by default refer to the value of the
 first band.

 This change means that we MUST remove the function's band parameters since
 they are not useful anymore.

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/1119#comment:1>
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