Hello Bob,

The BGN data, although rich in quantity, only has an accuracy of 1 minute of
a degree for the bulk of the data. If you view the data, you will see a grid
pattern evident of this. Not only will you find places with alternative
names on the same point but also places that are near each other. The
correct way to find places with alternative names is to use the ID and name
type fields.

Hope that helps.

Regards,
Warren Vick
Europa Technologies Ltd.
http://www.europa-tech.com

-----Original Message-----
From: Bob Hudson [mailto:[EMAIL PROTECTED] 
Sent: 27 March 2004 06:49
To: [EMAIL PROTECTED]
Subject: MI-L How to ignore duplicate points in the same file?


I  have a database of 50,000 or so villages and towns in Burma. Quite a few
have two or more names, and the database copes with this by putting  two or
more points on the same spot, each with a different name.  I am trying to do
nearest neighbour analysis on clusters of sites, using two copies of a file
of selected data. But if I select villages within a certain area, I get a
lot of duplicates, resulting in a statistically unviable neighbour to
neighbour value of 0 for each duplicated site. I guess one possibility is to
select my sites within the required area, then manually create a single new
point on each one in a new layer, just for the purposes of NN measurement,
but is there a less time-consuming way to do it?

The database, by the way, is from the US Geonet names server, a wonderful
free resource, and God bless those American taxpayers who have provided it
:-)
http://earth-info.nga.mil/gns/html/cntry_files.html

Bob Hudson
Archaeology Department, University of Sydney, Australia.
http://acl.arts.usyd.edu.au/~hudson/bobhpage.htm
Using MI 7, Win XP Pro



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