[GRASS-user] Flow Direction Map Question (r.stream.extract)

[stephen sefick]

The stream network that is  extracted is slightly different between
the two pieces of software, but they look close enough...  Thank you
all for your help.

Stephen

On Wed, Aug 18, 2010 at 1:08 PM, Jarek Jasiewicz <jarekj at amu.edu.pl> wrote:
> stephen sefick pisze:
>>
>> I am trying to use a direction map from taudem with the r.stream
>> modules.  I think the problem may be that -8 to 8 is the range of
>> value in the r.stream extract version and 1-8 in the taudem version.
>> I can generate one with r.stream extract with the flow accumulation
>> and the filled DEM from taudem.  The raster stream network are very
>> similar, but not totally the same.  Any help would be greatly
>> appreciated
>>
>>
>>  ------------------------------------------------------------------------
>>
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>>
>
> Taudem and r.watershed (and r.stream also) uses different direction coding
>
> If you want to use any network modeling software it shall use the same data.
>  Both direction and stream map must always match. However r.stream.extract
> can use any accumulation map including external software. You can use DEM
> and accum map created with Taudem (for example Dinf or D8-LFD) next generate
> network and direction map using r.stream.extract
>
> HTH
> J.
>
>



-- 
Stephen Sefick
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