[GRASS-user] map algebra logical operators on DCELL rasters not admitted? maybe docs should outline it

[Moritz Lennert]

On 19/10/15 21:16, Glynn Clements wrote:
>
> G. Allegri wrote:
>
>> Doing a logical operation with a DCELL raster within an if(x,a) statement
>> produces an error: "Incorrect argument types to function bitand()".
>
> First, you're confusing bitwise operators and logical operators. & and
> | are bitwise operators, while && and || (and &&& and |||) are logical
> operators.
>
> Second, both bitwise and logical operators only work on integer
> values. If you want to use floating-point values as boolean values,
> you need to explicitly convert them to integers (either via int(x) or
> round(x), or x==0.0, or abs(x)<1e-30, or whatever).

???

On my grass71 and grass64release, these work (using NC demo data set):

r.mapcalc "test = if(elevation == 100.0, 1)"
r.mapcalc "test = if(elevation > 100.0, 1)"

where elevation is FCELL.

Moritz