[GRASSLIST:679] height contour lines to raster

GRASS GRASS user
1

Hello,

I assume that the conversion of a vector map which contains height lines to a raster map is possible is possible with v.to.r? I ask because I would have to buy that file first.

Thanks für any reccomendation!

Cheers
Wolfgang

2

Probably didn't understand your question...
If you mean to import a vector file that has got an "height" value in is tab
and then convert to raster with value as the "height", i did it with no
problem...

Luca

Alle 11:54, mercoledì 12 aprile 2006, Wolfgang ha scritto:

Hello,

I assume that the conversion of a vector map which contains height lines
  to a raster map is possible is possible with v.to.r? I ask because I
would have to buy that file first.

Thanks für any reccomendation!

Cheers
Wolfgang

--
"E' molto più bello sapere qualcosa di tutto, che tutto di una cosa (Blaise
Pascal)."

GENTOO-GIS Development Team
jabber: casagrande@jabber.linux.it

3

that shape file contains height-contour lines, and I need it as regular raster map for an other software.

Cheers
Wolfgang

Luca Casagrande schrieb:

Probably didn't understand your question...
If you mean to import a vector file that has got an "height" value in is tab and then convert to raster with value as the "height", i did it with no problem...

Luca

Alle 11:54, mercoledì 12 aprile 2006, Wolfgang ha scritto:

Hello,

I assume that the conversion of a vector map which contains height lines
  to a raster map is possible is possible with v.to.r? I ask because I
would have to buy that file first.

Thanks für any reccomendation!

Cheers
Wolfgang

4

v.surf.rst (?)

Jachym

On Wed, Apr 12, 2006 at 01:05:24PM +0200, Wolfgang wrote:

that shape file contains height-contour lines, and I need it as regular raster map for an other software.

Cheers
Wolfgang

Luca Casagrande schrieb:
>Probably didn't understand your question...
>If you mean to import a vector file that has got an "height" value in is tab and then convert to raster with value as the
>"height", i did it with no problem...
>Luca Alle 11:54, mercoled? 12 aprile 2006, Wolfgang ha scritto:
>>Hello,
>>
>>I assume that the conversion of a vector map which contains height lines
>> to a raster map is possible is possible with v.to.r? I ask because I
>>would have to buy that file first.
>>
>>Thanks für any reccomendation!
>>
>>Cheers
>>Wolfgang

--
Jachym Cepicky
e-mail: jachym.cepicky@centrum.cz
URL: http://les-ejk.cz
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-----------------------------------------
OFFICE:
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Tel.: +420 545 134 514

5

On Wed, 12 Apr 2006 15:15:53 +0200
Jachym Cepicky <jachym.cepicky@centrum.cz> wrote:

v.surf.rst (?)

Worth of trying, but please expect problems (segmentation, artifficial
hollows, bulges). The more distant and clustered your input contour
lines are, the more of those artifacts. RST is great for fairly regular
input data, but problematic for most real elavation contour line
datasets. Of course, you might perfectly be happy with the result,
depending on what you expect of your DEM.

r.surf.contour is another way to go but also limited - it gets freaky
with highly clustered data, requires contour lines to be perfectly
continous, no elevation spots between the contour lines. Also it
creates integer DEM only, but this can be workedaround by
multiplying your input and dividing the output by the same number, say
1000.

For DEM interpolation I've personally been using nnbathy natural
neighbor interpolator, and I'm happy with it as it doesn't have all the
limitations of the two above (not mentioning IDW, no good for DEM from
disperse, clustered contour lines+points). Yet it is quite cumbersone to
make it use Grass data and import it's output back to Grass. If you'd
like to give a try, look at my rough how-to here:
http://grass.itc.it/pipermail/grass5/2006-April/022171.html

It would be great if natural neighbor interpolator was implemented in
Grass IMHO.

Any ideas how to improve my nnbathy-Grass "interface" are wellcome.

Cheers
Maciek

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