Importing polygons

[Mark S. Gregory]

I have received some data in which all of the areas are defined as polygons.
Even those areas which have common edges with other areas are contained as
complete polygons.

I can import the polygons into GRASS without any trouble.  I would, however,
like to convert the polygons to 'area edges' or segments in the manner that
GRASS stores areas.  Manually 'breaking the lines' in v.digit, then 'snapping'
the nodes, and removing the multiple lines (the common borders) is a tedious,
imprecise and often very complicated operation.  Am I missing something in
GRASS that would make this easier?

Any thoughts on the subject would be greatly appreciated.

Mark Gregory                    mg at adasn4.agr.okstate.edu
Oklahoma State University       (405)744-6417
Stillwater, OK 74078            (405)744-5269  fax