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<DIV dir=ltr align=left><SPAN class=324483316-26022009><FONT face=Arial
color=#0000ff size=2>Great advices!</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=324483316-26022009><FONT face=Arial
color=#0000ff size=2>Thanks to Mark and Moritz</FONT></SPAN></DIV><BR>
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<FONT face=Tahoma size=2><B>From:</B> grass-user-bounces@lists.osgeo.org
[mailto:grass-user-bounces@lists.osgeo.org] <B>On Behalf Of </B>M
S<BR><B>Sent:</B> donderdag 26 februari 2009 17:25<BR><B>To:</B> Christian
Braun<BR><B>Cc:</B> grass-user@lists.osgeo.org<BR><B>Subject:</B> Re:
[GRASS-user] DEM generation with v.surf.rst and isolines<BR></FONT><BR></DIV>
<DIV></DIV>I found this link from the GRASS wiki to be quite
helpful.<BR><BR><A
href="http://skagit.meas.ncsu.edu/~helena/grasswork/interpgen.html">http://skagit.meas.ncsu.edu/~helena/grasswork/interpgen.html</A><BR><BR><BR>Mark<BR><BR>
<DIV class=gmail_quote>On Thu, Feb 26, 2009 at 9:52 AM, Christian Braun <SPAN
dir=ltr><<A
href="mailto:christian.braun@tudor.lu">christian.braun@tudor.lu</A>></SPAN>
wrote:<BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Dear
list members,<BR><BR>I am currently working on the generation of a
hydrologic correct DEM.<BR>As base data I have isolines on a 20k scale and
60000 fix height points for whole Luxembourg (approx. 2500km^2)<BR>I tried
first v.surf.rst with the isoline input and it generates in the region of
valleys and plateaus artificial artifacts where it isn't able to gather
enough data in range of the isolines. It is clearly visible that these
represent the segmentation windows of the algorythm.<BR>Because of the
processing time (>20h for a small area) I shifted to v.to.points in
combination with v.surf.rst and try to include also the fix height points
for the interpolation.<BR>Can you tell me some suitable parameters to start
with for v.surf.rst in context of using isolines as input. In areas with
higher slope I have plenty of representation but I don't have data in flat
areas like valleys and plateaus.<BR><BR>Thanks in advance and greetings from
Luxembourg,<BR>Christian<BR><BR>------------------------------------------------------------<BR>Dipl.
Geogr. Christian Braun<BR>Tel: +352- 425991-608<BR>Mobil:
+49-179-6845896<BR>Mail: <A href="mailto:christian.braun@tudor.lu"
target=_blank>christian.braun@tudor.lu</A><BR><BR>Resource Centre for
Environmental Technologies,<BR>Public Research Centre Henri
Tudor,<BR>Technoport Schlassgoart,<BR>66 rue de Luxembourg,<BR>P.O. BOX
144,<BR>L-4002 Esch-sur-Alzette,
Luxembourg<BR><BR>_______________________________________________<BR>grass-user
mailing list<BR><A href="mailto:grass-user@lists.osgeo.org"
target=_blank>grass-user@lists.osgeo.org</A><BR><A
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