[GRASSLIST:7452] Re: r.terraflow failured

[David Finlayson]

I've been having trouble with this too. It seems that on my system,
r.terraflow cannot make files larger than 2Gb. I CAN create large
files on my system. For example:

dd if=/dev/zero of=test.tmp bs=1024k count=4000

creates a 4 GB file without problems. So it must be either something
intrinsic to the code in r.terraflow or a library it is sharing.
That's were my skills run out. I'm not a real programmer.

Interestingly enough, I met Dr. Toma when she was writing the original
version of this code for her PhD (I supplied her a big DEM to test the
algorithm). If we can't make progress on our own, I can send her an
email and see if she has any thoughts on the source of the problem.

David







On 7/4/05, Hamish <hamish_nospam at yahoo.com> wrote:
> orkun wrote:
> > >>At first time I tried to run r.terraflow in a small test area. I
> > >>failured. It gave this error:
> > >>
> > >>r.terraflow elev=el_5  filled=el5-filled  dir=el5-mfdir
> > >>swatershed=el5-watershed accumulation=el5-accu tci=el5-tci
> > >>
> > >>assigning directions on plateaus
> > >>File size limit exceeded
> > >>
> > >>
> > >>Could you tell me why ?
> 
> David Finlayson wrote:
> > >r.terraflow makes large temp files during the operation. Check the
> > >STREAM_DIR (defaults to /var/tmp) you assigned I would bet that one
> > >of those temp files exceeded 2 Gb. That seems to be the filesize
> > >limit on my distribution of linux.
> > >
> > >Davids
> 
> orkun wrote:
> > thank you
> > You are right.
> > that file made my disk full.
> > Although I used a small region for testing purposes. It produced
> > giantic files.
> > I do not know what will happen if I use whole region ?
> >
> > what do you suggest ?
> 
> 
> Try it and see what happens! (It has always worked for me)
> Worst case you run out of disk space again. Maybe the resolution was
> set way too high?
> 
> How big was the region that failed? (output of 'g.region -p'?)
> 
> 
> 
> Hamish
> 


-- 
David Finlayson
Marine Geology & Geophysics
School of Oceanography
Box 357940
University of Washington
Seattle, WA  98195-7940
USA

Office: Marine Sciences Building, Room 112
Phone: (206) 616-9407
Web: http://students.washington.edu/dfinlays