[GRASS-user] r.terraflow on massive DEM

Hi list, I'm trying to run r.terraflow on a very large DEM but I wander if it's __too large__. The region dimensions are: ncol=141114 nrow=140487 Data type = CELL The map is actually a reclass map of a raster that I imported using r.external. When I run r.terraflow I get: r.terraflow elevation

Re: [GRASS-user] r.terraflow on massive DEM

Hi Daniel, Try r.watershed with -m option in GRASS 7 (http://grass.osgeo.org/grass70/manuals/r.watershed.html) For me, on Ubuntu 12.04, that worked well on a DEM of that size. But be prepared to wait a couple of days for the result if you can not run it "in memory"... Cheers Stefan -- View th

Re: [GRASS-user] r.terraflow on massive DEM

I have never tried running r.terraflow on an integer raster, > I know that it works on decimal rasters. > > -Thayer > > > > -- > > Date: Mon, 12 Jan 2015 09:59:40 -0200 > From: Daniel Victoria > To: grass > Subject: [GRASS-user

Re: [GRASS-user] r.terraflow on massive DEM

a chance to make it >> down hill, otherwise you can get streams going no where near where they do >> in real life. I have never tried running r.terraflow on an integer raster, >> I know that it works on decimal rasters. >> >> -Thayer >> >> >> >> -- &g

Re: [GRASS-user] r.terraflow on massive DEM

have a problem.   -Thayer From: Daniel Victoria To: Charlie Shobe Cc: Thayer Young ; "grass-user@lists.osgeo.org" Sent: Tuesday, January 13, 2015 9:17 AM Subject: Re: [GRASS-user] r.terraflow on massive DEM Ouch! That means that probably, the person who importe

Re: [GRASS-user] r.terraflow on massive DEM

oung ; "grass-user@lists.osgeo.org" < > grass-user@lists.osgeo.org> > *Sent:* Tuesday, January 13, 2015 9:17 AM > *Subject:* Re: [GRASS-user] r.terraflow on massive DEM > > Ouch! That means that probably, the person who imported the data, > converted it to integer with

Re: [GRASS-user] r.terraflow on massive DEM

o make it >> down hill, otherwise you can get streams going no where near where they do >> in real life. I have never tried running r.terraflow on an integer raster, >> I know that it works on decimal rasters. >> >> -Thayer >> >> >> >> -- >> >> Da

Re: [GRASS-user] r.terraflow on massive DEM

contained after the decimal point to allow the flow a chance to make it >>> down hill, otherwise you can get streams going no where near where they do >>> in real life. I have never tried running r.terraflow on an integer raster, >>> I know that it works on decimal rasters.

Re: [GRASS-user] r.terraflow on massive DEM

ubject: Re: [GRASS-user] r.terraflow on massive DEM Charlie, I just downloaded some SRTM 1arc sec. from EarthExplorer. The data is supplied in 3 different file types, GeoTIFF, DTED or BIL and they are all in Integer values (Int16). No floating point elevation values. Cheers Daniel On Tue, Ja

Re: [GRASS-user] r.terraflow on massive DEM

gt;>> Halpin, Toma, Urban, Vitter, Wickremesinghe Efficient Flow Computation on >>>> Massive Grid Terrain Datasets Geoinformatica Volume 7 Issue 4, December >>>> 2003 >>>> Pages 283 - 313 ). My mid-2014 computer runs at about twice the speed >>

Re: [GRASS-user] r.terraflow on massive DEM

run it > >>>> may take several days to finish, this is more than twice the size of > the > >>>> Washington State DEM that took the authors 33 hours in 2003 (Arge, > Chase, > >>>> Halpin, Toma, Urban, Vitter, Wickremesinghe Efficient Flow > Computation on > >>>> Massive Grid Terrain Datasets G

Re: [GRASS-user] r.terraflow on massive DEM

shed a try. If that does not work, I'll see if I can >> >>> recompile. >> >>> >> >>> Thanks >> >>> Daniel >> >>> >> >>> On Mon, Jan 12, 2015 at 9:22 PM, Thayer Young >> >>> wrote: >> >

Re: [GRASS-user] r.terraflow on massive DEM

and asking > >> >>> me to > >> >>> change the dimension_type and recompile. > >> >>> > >> >>> I'll give r.watershed a try. If that does not work, I'll see if I > can > >> >>> recompile. > >>