[GRASS-user] Using r.resamp.stats for null values

[katrin eggert]

Just one question: is it possible to "count" number of cells with a certain
value (or nulls) from one scale that are being used to calculate each value
pixel of the target scale?
Thanks


2011/6/22 Glynn Clements <glynn at gclements.plus.com>

>
> katrin eggert wrote:
>
> > I just one to confirm one thing. If I'm using r.resamp.stats with
> > *mode *option.
> > If the most frequent value is a null, will i have a null value in the
> ouput?
>
> No.
>
> With the -n option, the output is null if any input cell is null.
> Without the -n option, most aggregates (including "mode") ignore null
> cells; you'll only get a null result if all input cells are null.
>
> IIRC, the only reason that nulls are retained in the array passed to
> the aggregate functions is that some of them (e.g. interspersion,
> regression) consider the cell's position within the array, and having
> the caller discard nulls beforehand would interfere with this.
>
> --
> Glynn Clements <glynn at gclements.plus.com>
>
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