Re: [GRASS-user] stream network

On Wed, Mar 2, 2016 at 8:42 PM, Janet Choate wrote: > Hi Will, > When running r.watershed on a small 35 hectare watershed, it produces a > fully connected stream network. However, when running r.watershed on a 6400 > hectare watershed, the stream network is not fully connected.

Re: [GRASS-user] stream network

Michel, thank you - i'll try your r.mapcalc and vector suggestions. Janet On Thu, Mar 3, 2016 at 8:22 AM, Michel Wortmann wrote: > HI Janet, > can you specify what you mean by 'fully connected stream network'? > 'connected' doesnt mean much on a raster map or did you

Re: [GRASS-user] stream network

Stefan, unfortunately - it's not something that is apparent by appearance. the problem was discovered after using the raster map as an input to another program - then it became clear that there were places where there were no upstream or downstream neighbors to some segments. thanks, Janet On

Re: [GRASS-user] stream network

HI Janet, can you specify what you mean by 'fully connected stream network'? 'connected' doesnt mean much on a raster map or did you convert it a vector? I would try to build your stream network from the accumulation raster map by thresholding it with a certain catchment size (in cells). Eg.

Re: [GRASS-user] stream network

Hi Janet, can you provide a screenshot of the river network, I think that helps to understand what is going on in your specific case?! Cheers, Stefan On 02/03/16 20:42, Janet Choate wrote: > Hi Will, > When running r.watershed on a small 35 hectare watershed, it produces a > fully connected

Re: [GRASS-user] stream network

Hi Will, When running r.watershed on a small 35 hectare watershed, it produces a fully connected stream network. However, when running r.watershed on a 6400 hectare watershed, the stream network is not fully connected. No preprocessing with regards to merging different raster maps, however, I did

Re: [GRASS-user] stream network

Hi Janet, Can you give some more information about what you mean by larger watershed basins? Did you do any preprocessing of the elevation raster before you tried to extract the stream networks? Were you using an elevation raster that had been merged from different rasters? I've ran into

[GRASS-user] stream network

Hi GRASS community, When creating a stream network with r.watershed, I end up with some isolated stream segments - particularly in larger watershed basins. Does anyone know how to generate a stream network that is fully connected, or how to correct this issue? thank you, Janet

Re: [GRASS-user] stream network extraction

Hi Markus, hi all, I'm trying to compilate the code of r.stream.extract (from addOns) but when I run make command it gives me this error: annal...@annalisa-laptop:~/grass_dev64/raster/r.stream.extract$ sudo make test -d OBJ.i686-pc-linux-gnu || mkdir -p OBJ.i686-pc-linux-gnu gcc

Re: [GRASS-user] stream network extraction

Hi, 2009/9/24 annagrass6 annagra...@gmail.com: Hi Markus, hi all, I'm trying to compilate the code of r.stream.extract (from addOns) but when I run make command it gives me this error: annal...@annalisa-laptop:~/grass_dev64/raster/r.stream.extract$ sudo make test -d OBJ.i686-pc-linux-gnu ||

Re: [GRASS-user] stream network extraction

Hi Markus, That is what was missing in stream-network analyzes! Great to have this! I didnt have a deeper look yet, but I will test and probably enjoy the script (in fast C-code). Thank you for that! Achim Markus Metz schrieb: Hi all, in grass-addons is a new module for clean stream

Re: [GRASS-user] stream network extraction

Markus Metz pisze: Hi all, in grass-addons is a new module for clean stream network extraction from flow accumulation. It can extract streams from accumulation maps generated with any method (D8, FD8, D-Inf, DEMON, etc) and any software, granted that exactly the same elevation map is

Re: [GRASS-user] stream network extraction

Jarosław Jasiewicz wrote: rest of r.stream* modules including new r.stream.stats for Hortonian statistics are now available by grass addons page and by grass add-ons svn repository. I actually move tutorial on r.stream* to grass wiki page. Great, IMHO the tutorials on your website are very

Re: [GRASS-user] stream network extraction

Markus Metz pisze: Jarosław Jasiewicz wrote: rest of r.stream* modules including new r.stream.stats for Hortonian statistics are now available by grass addons page and by grass add-ons svn repository. I actually move tutorial on r.stream* to grass wiki page. Great, IMHO the tutorials on

[GRASS-user] stream network extraction

Hi all, in grass-addons is a new module for clean stream network extraction from flow accumulation. It can extract streams from accumulation maps generated with any method (D8, FD8, D-Inf, DEMON, etc) and any software, granted that exactly the same elevation map is provided that was used to