[GRASS-user] Estimating import time for large data file

[Markus Neteler]

Rich,

On Sun, May 31, 2020 at 6:31 PM Rich Shepard <rshepard at appl-ecosys.com> wrote:
>
> On Sun, 31 May 2020, Markus Neteler wrote:
>
> > ogr2ogr
> >   -simplify <tolerance>
> >    Distance tolerance for simplification. Note: the algorithm used
> > preserves topology per feature, in particular for polygon geometries, but
> > not for a whole layer.
>
> Markus,
>
> Thanks for confirming this approach.

I didn't confirm at all :-)
It was just an information or warning.

> > ... keep in mind that AFAIK this may damage the topology (i.e. gaps
> > and slivers may arise between polygons).
> > So, select the <tolerance> with care...
>
> Given that I have no experience selecting tolerances for simplfy please
> suggest what I should read to make an informed first guess.

I'd stick to submeter but I don't know what data you are working with
nor what their resolution/scale is...

Markus