[GRASS-dev] Test suite for GRASS - proposal, discussion welcome

Glynn Clements glynn at gclements.plus.com
Thu Jun 9 20:29:34 EDT 2011

Moritz Lennert wrote:

> >> v.random output=random_points n=100
> >> v.info -t random_points>  result
> >
> > If the framework understands vector maps, it shouldn't be necessary to
> > use v.info; it should be able to compare the random_points map to
> > random_points.ref.
> But how to compare two randomly generated maps ? Unless the system is 
> not really random, the maps _should_ be different.

Ugh; v.random should have a seed= option (or something) to allow
repeatability. Or at least an option to disable seeding with the PID.

For comparison, r.mapcalc's rand() is seeded from the GRASS_RND_SEED
environment variable. If that isn't set, it isn't explicitly seeded
(i.e. the default seed is used). If you want different results for
each run, you need to explicitly change GRASS_RND_SEED each time.

Glynn Clements <glynn at gclements.plus.com>

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