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 calculate flow accumulation. In case of r.terraflow, that would be the flooded (filled) output elevation map, not the elevation map used as input for r.terraflow. For e.g. TAS flow accumulation as input, it must be the elevation map used within TAS to calculate flow accumulation.
r.stream.extract output is available as raster and vector with unique stream IDs. The vector is a complete network with stream segments and points for stream heads, confluences and outlets. The raster output can be used as input for the r.stream.* modules of Jarek, also in grass-addons.
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 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
calculate flow accumulation. In case of r.terraflow, that would be the
flooded (filled) output elevation map, not the elevation map used as
input for r.terraflow. For e.g. TAS flow accumulation as input, it must
be the elevation map used within TAS to calculate flow accumulation.
r.stream.extract output is available as raster and vector with unique
stream IDs. The vector is a complete network with stream segments and
points for stream heads, confluences and outlets. The raster output can
be used as input for the r.stream.* modules of Jarek, also in grass-addons.
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 calculate flow accumulation. In case of r.terraflow, that would be the flooded (filled) output elevation map, not the elevation map used as input for r.terraflow. For e.g. TAS flow accumulation as input, it must be the elevation map used within TAS to calculate flow accumulation.
r.stream.extract output is available as raster and vector with unique stream IDs. The vector is a complete network with stream segments and points for stream heads, confluences and outlets. The raster output can be used as input for the r.stream.* modules of Jarek, also in grass-addons.
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.
I have areas with unique cats and a column "value" as integer.
I want to reclass from column "value"
and ->here is the problem:
keep the value information to identify the areas.
In the manual it says:
No table is created for reclassed layer if column option is used and
column type is integer (there is nothing which could be written to the
table).
But couldn't be there a table with value-integer as cat?
So how can I identify areas with the "value"?
Thanks,
Achim
PS:
workaround would be:
v.to.rast with old values
update centros of reclassed map from that raster map
-> but it seems a bit in-elegant..
PS:
workaround would be:
v.to.rast with old values
update centros of reclassed map from that raster map
-> but it seems a bit in-elegant..
...and which is a bit complicated as centroids cannot be used in
v.what.rast...
...and conversion into points produces more than one point for some
centroids (where one cat has more than two separate areas), so
v.what.rast produces NULLs here...
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 helpful and show nicely all the various results the new r.stream.* modules can produce. Maybe a link to the wiki page can be added to the manuals?
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 helpful and show nicely all the various results the new r.stream.* modules can produce. Maybe a link to the wiki page can be added to the manuals?
I havent found anything about playing with the common geom multipolygon
in GRASS. I think that is what I need and what I thought I could handle
with v.reclass. But it does not work.
-Is there something in GRASS to create multipolygons?
-Do they have one centroid or multiple with the same cat (as I thought)
Any suggestions are very welcome
achim
achim schrieb:
PS:
workaround would be:
v.to.rast with old values
update centros of reclassed map from that raster map
-> but it seems a bit in-elegant..
...and which is a bit complicated as centroids cannot be used in
v.what.rast...
...and conversion into points produces more than one point for some
centroids (where one cat has more than two separate areas), so
v.what.rast produces NULLs here...
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:
annalisa@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 -I/home/annalisa/grass_dev64/dist.i686-pc-linux-gnu/include -g -Wall -I/usr/local/include -DPACKAGE="“grassmods”" -I/home/annalisa/grass_dev64/dist.i686-pc-linux-gnu/include -o OBJ.i686-pc-linux-gnu/close.o -c close.c
close.c: In function ‘close_streamvect’:
close.c:33: warning: format not a string literal and no format arguments
close.c:152: warning: format not a string literal and no format arguments
close.c:184: warning: format not a string literal and no format arguments
close.c:210: warning: format not a string literal and no format arguments
close.c:218: warning: format not a string literal and no format arguments
close.c:221: error: too few arguments to function ‘Vect_build’
close.c: In function ‘close_maps’:
close.c:242: warning: format not a string literal and no format arguments
make: *** [OBJ.i686-pc-linux-gnu/close.o] Error 1
“close.c:221: error: too few arguments to function ‘Vect_build’”
Where am I going wrong?
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 helpful and show nicely all the various results the new r.stream.* modules can produce. Maybe a link to the wiki page can be added to the manuals?
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:
annalisa@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 -I/home/annalisa/grass_dev64/dist.i686-pc-linux-gnu/include -g -Wall
-I/usr/local/include -DPACKAGE=\""grassmods"\"
-I/home/annalisa/grass_dev64/dist.i686-pc-linux-gnu/include -o
OBJ.i686-pc-linux-gnu/close.o -c close.c
close.c: In function ‘close_streamvect’:
close.c:33: warning: format not a string literal and no format arguments
close.c:152: warning: format not a string literal and no format arguments
close.c:184: warning: format not a string literal and no format arguments
close.c:210: warning: format not a string literal and no format arguments
close.c:218: warning: format not a string literal and no format arguments
close.c:221: error: too few arguments to function ‘Vect_build’
close.c: In function ‘close_maps’:
close.c:242: warning: format not a string literal and no format arguments
make: *** [OBJ.i686-pc-linux-gnu/close.o] Error 1
"close.c:221: error: too few arguments to function ‘Vect_build’"
Where am I going wrong?
update your GRASS. In r34288 was eliminate non-standard logging
mechanism, currently Vect_build() takes only one argument - pointer to
Map_info structure.