[GRASS-user] announcement of strahler stream order analysis

Jarek Jasiewicz jarekj at amu.edu.pl
Tue Jul 28 11:46:17 EDT 2009

try, I don't know I haven't  LL location to test it
but it shoud work
program do not use any inforamtuon about units and units conversion


Milton Cezar Ribeiro pisze:
> Hi Jarek
> Can use this on a LatLong mapset where my unit is not meters?
> Thanks for the effort!
> milton
> 2009/7/26 Jarek Jasiewicz <jarekj at amu.edu.pl <mailto:jarekj at amu.edu.pl>>
>     Hi list!
>     I just finish first version of new grass module r.stream. Module
>     is regular Grass module, written in C an has no addational
>     dependencies. It was compiled with GRASS65 devel  downloaded in
>     last  two week. Source code you can find here:
>     http://heretic.livenet.pl/heretic/r.stream.tar.gz
>     Module compiles and seems to work. Analysis was tested only on one
>     dataset.
>     To compile it copy r.streams directory to your grassXX../raster/
>      cd r.stream run make and make install
>     What module calculate:
>     - strahler stream order
>     - shreeve stream magnitude
>     - class of topological elements of drainage networks
>     Module use r.watershed outputs: SDF flow direction and SDF stream
>     network.
>     Analysis of r.stream shall be run on same regions setings as
>     r.watershed. If no, run g.region rast=your_dir_file first. For now
>     module do not check if region and rasters are identical. It is
>     planned to add in nearest feature. It also do not check if dirs
>     and streams are SDF result. Threre are no addational description.
>     It will be added after testing.
>     It works only on cells data. Floating points data are not allowed
>     (and have no sense).
>     Module is quite fast. 3000 x3000 cells all three analysis runs no
>     more than 30 s. on AMD 3800 2GB, Ubuntu 8.04
>     Module is part of comprehensive project which will add full Horton
>     analysis and some addational terrrains analysis to Grass. More
>     details in the feature. Any cooperation is welcome. The next
>     module I plan is directional vectorisation of stream network.
>     For now module is available only form web address pointed below.
>     After testing and removing critical errors it will be added to
>     grass add-ons (or maybe to main branch?).
>     Any coments, improvements and critics is very welcome.
>     More advanced Grass developers: Please check my code. Its funny,
>     but I don't know C.
>     General code is based on GRASS r.topindex module (by Keith Beven
>     and Huidae Cho, strongly modified)
>     Strahler stream order algorithm from Saga GIS (by Victor Olaya,
>     modified)
>     Shreeve stream magnitude and class of topological network are my
>     own ideas
>     Test and enjoy.
>     Jarek Jasiewicz
>     Adam Mickiewicz University, Poznan
>     Geoecology and Geoinformation Institute
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