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<DIV><FONT face=Arial size=2>Hi all,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I have recently joined the user group and I'm
working on LiDAR data.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I have worked alot of things out from the book and
fiddling but have a question regards this.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I am running GRASS GIS 6.4.0svn (the one that came
out last week) on an Intel quad core 6600 with 2gb RAM.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I have seperated my data into 1000mx1000m which
have around 1.5 million points per tile.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I use the -tbzr on v.in.ascii and v.build after for
topology. I have also utilised the sqlite db.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>After running v.outlier on first and last returns,
the time come for edge detection.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I run this module (v.lidar.edgedetection) and it
works (only using 25% of cpu as per usual (guessing there is no quad cpu support
= shame)) However, I have not finished a process yet as it writes at about 1kb
per second, using 1% of cpu.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Is it supposed to be this slow? is there a bug? The
tile as .txt/.las is c.47Mb. Does the edge file equate to a similar size, e.g.
will it take about 47000 seconds to write the file? Is there a rough
percentage of the size of edge file compared to original txt file? I notice
it is also writing to the sqlite.db at the same time.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Have I done something wrong?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I would appreciate some feedback of other peoples
experiences of v.edgedetection in this version and earlier version of win
GRASS.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Cheers, and hope someone can help</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>John</FONT></DIV>
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