[GRASS-dev] quickest way to test whether a raster contains any non-null values in the current computational region ?

[Markus Metz]

On Fri, Oct 19, 2018 at 4:04 PM Moritz Lennert <mlennert at club.worldonline.be>
wrote:
>
> On 19/10/18 15:48, Michel Wortmann wrote:
> > Hi Moritz,
> > How about this:
> >
> > info = grass.parse_command('r.univar', map='raster_xyz', flags='g')
> > print(int(info['n']), int(info['null_cells']))
>
> Thanks !
>
> Yes, this is one option. I was wondering if there was any faster option
> than actually having to read the map in the whole region with r.univar,
> but probably there isn't.

You need a module that reads the whole map, and the fastest way to get the
number of non-null values is most probably r.univar -g, as mentioned by
Michel Wortmann.

Markus M

>
> Moritz
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