[GRASSLIST:7848] Re: visualize DEM error
temiz at deprem.gov.tr
Thu Aug 11 02:16:22 EDT 2005
Dylan Beaudette wrote:
> Couple ways that are outlined in this book  suggest making
> histograms of elevation and aspect data. if you see spikes at regular
> intervals in either graph then you have some artifacts - possibly due
> to the use of contours as your input data. You can do this with the
> GRASS-R interface in a couple of minutes.
> Another quick check, does your DEM support realistic flow patterns,
> when modeled with something like r.terraflow? i.e. do numerous sinks
> and dams cause water to move with no outlet, when expert knowledge of
> the area suggests otherwise? Comparison with an alternate source of
> stream data may also shed some light on the quality of the DEM.
> How did you create the DEM, and from what type of source ?
>  J. P. Wilson and J. C. Gallant, editors. Terrain Analysis. John
> Wiley and Sons Inc., New York, 2000.
> Dylan Beaudette
> Soils and Biogeochemistry Graduate Group
> University of California at Davis
> On Aug 10, 2005, at 12:46 AM, orkun wrote:
>> how can I visualize DEM error ?
>> how can I interpret whether DEM which I have created is correct ?
>> could you give me hints ?
>> Ahmet Temiz
>> XamimeLT - installed on mailserver for domain @deprem.gov.tr
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>> Earthquake Research Dept.
>> of General Directorate of Disaster Affairs.
>> Bu e-postadaki fikir ve gorusler gonderenin sahsina ait olup, yasal
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>> nitelikte degildir.
thank you Dylan
I used v.surf.rst to create DEM.
I have a topographic contour map as source.
XamimeLT - installed on mailserver for domain @deprem.gov.tr
Queries to: postmaster at deprem.gov.tr
The views and opinions expressed in this e-mail message are the sender's own
and do not necessarily represent the views and the opinions of Earthquake Research Dept.
of General Directorate of Disaster Affairs.
Bu e-postadaki fikir ve gorusler gonderenin sahsina ait olup, yasal olarak T.C.
B.I.B. Afet Isleri Gn.Mud. Deprem Arastirma Dairesi'ni baglayici nitelikte degildir.
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