[postgis-users] Reclassify a Slope Surface

[Pierre Racine]

> For ST_MapAlgebraExpr,: "you can use the term [rast] to refer to the pixel value
> of the original band"
> Does this mean rast can be used as the value for each individual pixel?
> 
> For example, something like (max.value - [rast]) / max.value. Or have I
> misinterpreted how [rast] can be used?

You have well interpreted. However you have to construct the expression as a string parameter casting the maxvalue to text.

Pierre