[GRASS-user] g.region -a: what's it supposed to do?

[Ken Mankoff]

Hello again,

Please disregard the previous message. I've read the docs again and "even multiples of the resolution" is the key part. I get it now, and why I'm seeing the behavior from the commands below.

  -k.

On 2020-11-27 at 04:13 -08, Ken Mankoff <mankoff at gmail.com> wrote...
> My previous understanding is that if I set e,w,n,s AND rows,cols AND
> res, and they don't all agree, then res takes precedence if -a is set,
> and otherwise res is subject to the other six paramaters.
> Alternatively, if just setting e,w,n,s and res, and the e,w res does
> not match the n,s res, then setting -a would adjust things. But when
> everything agrees, why is -a shifting the bounds?
>
> grass -c EPSG:3413 G_tmp
>
> g.region w=-638956 e=856044 s=-3354596 n=-655596 res=1000 -p
> eval $(g.region -g)
> echo $(( ($n - $s)/1000 ))
> echo $(( ($e - $w)/1000 ))
>
> # why does this shift things?
> g.region w=-638956 e=856044 s=-3354596 n=-655596 res=1000 -pa
>
>
> I don't see previous questions about this when searching "g.region resolution align bounds site:lists.osgeo.org/pipermail/grass-user/" on Google.
>
>
> Thanks,
>
>    -k.