[GRASS5] [bug #2690] (grass) System Response when no colortable is present

Glynn Clements glynn at gclements.plus.com
Mon Nov 15 20:33:48 EST 2004

Gordon Keith wrote:

> > That's a separate problem; v.to.rast explicitly sets a random
> > colourtable.
> >
> > In the test cases I've tried, it seems to work ok. If you know of a
> > case which doesn't work, please submit a bug report with sufficient
> > details to allow reproduction.
> The case I have involves floating point data.
> v.in.ascii in=bathydata out=test
> d.rast test
> seems to display points only where test==int(test)

Right. The random colour table only defines colours for discrete
(integral) values; most of the others define one or more ranges which
cover the entire range of the data.

> r.colors test color=random
> gives the message:
> ERROR: Can't make random color table for floating point map
> so v.to.rast probably needs to do something sensible with floating
> point maps.

It should probably just not bother creating a colour table. The
default rainbow colour table should be adequate (it works with
floating-point maps, and it doesn't include black or white, so there's
no chance of the vectors accidentally blending with the background).

Glynn Clements <glynn at gclements.plus.com>

More information about the grass-dev mailing list