[GRASS-user] r.terraflow problem

[Markus Metz]

Markus Metz wrote:
>>
>> I thought that r.terraflow scales better to larger DEMs than r.watershed,
>> but I'll try r.watershed next.
>
> It's more or less on par now when using the disk swap mode of
> r.watershed.

Oops, only in grass7. In grass64, r.watershed in disk swap mode is
still a bit slower than r.terraflow.

Markus M

>
>>
>> Markus Metz wrote:
>>>
>>> Aleksey Naumov wrote:
>>> > Dear GRASS users,
>>> >
>>> > I am trying to run r.terraflow in GRASS 6.4.0svn (GIS library revision:
>>> > 37101 (2009-05-10)) provided as part of the OSGeo4W bundle on WinXP. The
>>> > command prints some output, which looks normal, and then exits right
>>> > away
>>> > without doing anything.
>>> >
>>> > Here is the command and the output I get:
>>> >
>>> > (Thu Jul 29 13:32:43
>>> > 2010)
>>> > r.terraflow --overwrite --verbose elevation=dem at PERMANENT filled=tf_dem
>>> > direction=tf_fdir swatershed=tf_sink accumulation=tf_fac tci=tf_tci
>>> > STREAM_DIR=C:/Active_projects/tmp/tf
>>> > cell dem header compatible with region header
>>> > stats.out: File exists
>>> > Elevation stored as FLOAT (4B)
>>> > Region size is 13000 x 9200
>>>
>>> This is 119.6 million cells, too large for wingrass, r.terraflow will
>>> most likely abort because the temporary files become too large (no
>>> large file support in wingrass). Try r.watershed instead.
>>>
>>> > STREAM temporary files in C:/Active_projects/tmp/tf  (THESE
>>> > INTERMEDIATE STREAMS WILL NOT BE DELETED IN CASE OF ABNORMAL
>>> > TERMINATION OF THE PROGRAM. TO SAVE SPACE PLEASE DELETE
>>> > THESE FILES MANUALLY!)
>>> > file stats.out exists - renaming.
>>>
>>> Either manually delete the file stats.out first before running
>>> r.terraflow or, as suggested in the other reply, update grass.
>>>
>>> Markus M
>>
>>
>