About a week ago I posted a message regarding v.trim removing single
polygon islands from vector maps I was processing with a trim factor
of 0.  After some ruminating on the subject I think I may have come
up with a possible reason why:

Since v.trim is removing all nodes that have only 2 lines connected to
them, it ends up removing all nodes for that polygon.  And without any
nodes, the polygon doesn't exist.

Does this seem like a reasonable explanation to you?  I'm not a GRASS
programmer, so this is only a theory.  I'd appreciate any help you can
offer.

Bruce Nielsen                      VOICE:    (317) 290-3211
Computer/GIS Specialist            FAX:      (317) 290-3225
USDA-Soil Conservation Service     INTERNET: bnielsen@in1000.attmail.com
6013 Lakeside Blvd.
Indianapolis, IN 46278


