Questions on calculating minimum distance between polygons and map attributes after

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Questions on calculating minimum distance between polygons and map attributes after

Kristian Skrede Gleditsch
Dear all,

I have a research project for which I would like to find the minimum
distance between nation states. I have previously developed a data set on
minimum distances for states within 1000 km based on manual coding (see

However, since manual coding may suffer from measurement error and I ideally
would like to have data for pairs of state more than 1000 km apart I would
like to generate a new version of the minimum distance data from GIS
software and cartographic data.

What I would like to do is to try to use an algorithm to determine the
shortest distance between points on two states? outer boundaries, with each
state defined either as a polygon or union of polygons. I would appreciate
any suggestions comments from list members on whether the project is
technically feasible in GRASS and R. I am running GRASS 5.0 under Redhat
Linux 7.0, will upgrade to newer versions if need be.

At this point I have ARC info coverages for boundary changes from 1945 to
the present. I have tried to import this into GRASS with with
somewhat mixed results. Although I am able to display the vector map, it is
not clear to me how I can identify attributes or polygons. As far as I
understand these must be imported separately, but so far I have not been
able to figure out how to do this. I tried to follow Netler and Mitasova
book, but I was not able to get the procedure that they listed to work.

I would be grateful if anyone could point me to practical introductions or
examples in the use of and how to retrieve the map attributes from
the ArcInfo coverages in GRASS.

Kristian Skrede Gleditsch
Assistant Professor
Department of Political Science
University of California, San Diego
La Jolla, CA 92093-0521, USA
Tel: (858) 822 0535, Fax: (858) 534 7130
Email: kgleditsch at