[GRASS-dev] [bug #4827] (grass) Building topology for vector is incredibly slow

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this bug's URL: http://intevation.de/rt/webrt?serial_num=4827
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Subject: Building topology for vector is incredibly slow

Platform: Mac OSX
grass binary for platform: Downloaded precompiled Binaries
GRASS Version: 6.1.cvs_060624

Raffaele Morelli
I am working with several vector files from Italy I have imported from shape files with v.in.ogr.
Those data comes with ISTAT census, so they are organized in several small polygons for each town (called "sezioni").
I wanted to produce a global national vector with polygons representing towns instead small areas inside towns, so I started running a shell script with all the "v.extract -d .. .... " to dissolve boundaries from the same town. Finally I came into a national vector map after patching the regional maps previously obtained gatering towns from the same region.


After this I launched a v.clean to remove duplicates,small angles and break poligons. The process runs normally but when it's time to build topology at the end of v.clean the process is incredibly slow.
After 50 minutes is still running and the building areas progress is at 33%!!!

is this 'normal'?

I hope I exposed clearly enough to help you.
Thanx anyway

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