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<DIV><FONT face=Arial size=2>Hi all,</FONT></DIV>
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<DIV><FONT face=Arial size=2>for reducing the volume a rather large vectormap
(16.000 polygons) I wrote a grass5-script which </FONT></DIV>
<DIV><FONT face=Arial size=2>1. automatically generates a rectangle around the
current region (works at least with
tmerc,lat/long,lambert-projection)</FONT></DIV>
<DIV><FONT face=Arial size=2>2. cuts the original map with v.cutter</FONT></DIV>
<DIV><FONT face=Arial size=2>3. runs v.spag -i and v.support </FONT></DIV>
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<DIV><FONT face=Arial size=2>This works fine, but only sometimes. I cut country
outlines, DEM-contours (created with r.contour) and a map with soil properties
and I noticed that the size of the region seems to influence v.cutter. If, for
example, i cut parts of the coastline of norway, v.cutter works for a region
with a maximum width of 6 geographic degrees, a wider region produces an empty
vector file. The DEM-contour-map, which seems to contain much more data, can be
cut using a region of any size.</FONT></DIV>
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<DIV><FONT face=Arial size=2>Thus it appears that certain combinations of
datafile and cutterfile cause v.cutter to generate no vectors at all. I don't
see any rule as to when it works an when it doesn't so I think that
this might be some bug in v.cutter.</FONT></DIV>
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<DIV><FONT face=Arial size=2>greetings, Stefan</FONT></DIV></BODY></HTML>