[GRASS-user] change the cell value of a geotiff

[Hamish]

maven apache wrote:
> I have a geotiff now, and some cells have a not-expected
> value, so I want to Interpolation them, and I notice that
> there is a command named r.fillnull, however the cell to be
> changed is not null, so I want to :
> 1) change the special  cell value to null
> 
> 2) use the r.fillnull to Interpolation.
> 
> The problem is I do not know how to do the step 1 with
> grass, anyone can do me a favor?


try r.null.


Hamish