[GRASS-user] r.drain problem when flow reach the border

[Markus Metz]

Markus Metz wrote:
>
> I am going to backport r.cost/r.walk/r.drain from 6.5 to 6.4.

Done in r54470-1.

>
> Happy new year,
>
> Markus M
>
>>
>> best wishes
>>
>> miltinho
>>
>>
>> 2012/12/30, Markus Metz <markus.metz.giswork at gmail.com>:
>>> On Sun, Dec 30, 2012 at 8:59 PM, Milton Cezar Ribeiro
>>> <miltinho.astronauta at gmail.com> wrote:
>>>> Hi Rashad
>>>>
>>>> I tested with the trunk svn, but apparently it still not worked to me.
>>>> Are you able to test with my datased?
>>>>
>>>> https://www.yousendit.com/download/UW16RE9zTkxlM1JBSXNUQw
>>>
>>> What are the commands you used? I found
>>> r.drain input=custo_aux_cost output=custo_aux_cost_drain
>>> vector_points=map_target_pt
>>>
>>> You need to also provide a direction map with the indir option of r.drain.
>>>
>>> Markus M
>>>
>>>>
>>>> Thanks!
>>>>
>>>> miltinho
>>>>
>>>> 2012/12/27, Mohammed Rashad <mohammedrashadkm at gmail.com>:
>>>>> Hi Milton,
>>>>>
>>>>> I think this fix will solve the problem[0]. For elevation data there
>>>>> might
>>>>> be cases where no path exists ie, only single pixel is the selected path.
>>>>> I
>>>>> had tested it by myself and it worked.
>>>>>
>>>>> Please apply the patch and let me know.
>>>>>
>>>>> If any problem comes in compilation or doing r.drain let me know. It
>>>>> will
>>>>> be great if you can share the test data you are using in case not
>>>>> working
>>>>> after applying the patch
>>>>>
>>>>> [0] http://trac.osgeo.org/grass/attachment/ticket/1840/r.drain.diff
>>>>> [1] http://trac.osgeo.org/grass/attachment/ticket/1840/drain.c
>>>>>
>>>>>
>>>>> On Thu, Dec 27, 2012 at 2:31 AM, Milton Cezar Ribeiro <
>>>>> miltinho.astronauta at gmail.com> wrote:
>>>>>
>>>>>> Hi Mohamed and Markus
>>>>>>
>>>>>> Mohamed, thanks for your reply, I will wait for a solution within GRASS
>>>>>> :-)
>>>>>>
>>>>>> Markus, thanks for your reply,. Sorry  but I disagree a tiny bit,
>>>>>> because is expected that between a source and target I will find a
>>>>>> solution with the Least Cost path. Do you think that is there any
>>>>>> situation where a least cost between source and target will not be
>>>>>> found? Maybe if other software provide the soluction, although is not
>>>>>> the bestest option, I prefere receive one complete output than a
>>>>>> broken one.
>>>>>>
>>>>>> Happy new year!
>>>>>>
>>>>>> miltinho
>>>>>>
>>>>>> 2012/12/23, Markus Metz <markus.metz.giswork at gmail.com>:
>>>>>> > On Sun, Dec 23, 2012 at 7:07 PM, Milton Cezar Ribeiro
>>>>>> > <miltinho.astronauta at gmail.com> wrote:
>>>>>> >> Dear all,
>>>>>> >>
>>>>>> >> I am running a least cost path analysis combining r.cost and
>>>>>> >> r.drain.
>>>>>> >> But on some cases, when the least cost path between source and
>>>>>> >> target
>>>>>> >> reach the border of my map, r.drain stop on that position, and
>>>>>> >> target
>>>>>> >> point isn´t reached.
>>>>>> >
>>>>>> > This is correct because at the borders, the direction can not be
>>>>>> > determined, the path could lead out of the current region, you can
>>>>>> > not
>>>>>> > tell.
>>>>>> >
>>>>>> > Running on other softwares the algorithms the
>>>>>> >> source and target is connected using edges without problem.
>>>>>> >
>>>>>> > If in doubt, I would call it a bug in that other software.
>>>>>> >
>>>>>> >>
>>>>>> >> Any hint are welcome.
>>>>>> >
>>>>>> > Try to expand the current region
>>>>>> >
>>>>>> > Markus M
>>>>>> >
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Miltinho - mcr at rc.unesp.br
>>>>>> Laboratório de Ecologia Espacial e Conservação - LEEC
>>>>>> Depto de Ecologia - UNESP - Rio Claro
>>>>>> Av. 24A, 1515- Bela Vista
>>>>>> 13506-900 Rio Claro, SP, Brasil
>>>>>>
>>>>>> Fone: +55 19 3526-9647 (office)  19 3526-9680 (lab)
>>>>>> Cel: 19 9853-3220 / 19 9853-5430
>>>>>>
>>>>>> Depto Ecologia http://www.rc.unesp.br/ib/ecologia/
>>>>>>
>>>>>> PG ECO & BIODIV
>>>>>> http://www.rc.unesp.br/ib/ecologia/posbiodiversidade/index.php
>>>>>>
>>>>>> CV
>>>>>> http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4792988H6&mostrarNroCitacoesISI=true&mostrarNroCitacoesScopus=true
>>>>>>
>>>>>> Google citations http://scholar.google.com/citations?user=OWX_2eAAAAAJ
>>>>>> _______________________________________________
>>>>>> grass-user mailing list
>>>>>> grass-user at lists.osgeo.org
>>>>>> http://lists.osgeo.org/mailman/listinfo/grass-user
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Regards,
>>>>>    Rashad
>>>>>
>>>>
>>>>
>>>> --
>>>> Miltinho - mcr at rc.unesp.br
>>>> Laboratório de Ecologia Espacial e Conservação - LEEC
>>>> Depto de Ecologia - UNESP - Rio Claro
>>>> Av. 24A, 1515- Bela Vista
>>>> 13506-900 Rio Claro, SP, Brasil
>>>>
>>>> Fone: +55 19 3526-9647 (office)  19 3526-9680 (lab)
>>>> Cel: 19 9853-3220 / 19 9853-5430
>>>>
>>>> Depto Ecologia http://www.rc.unesp.br/ib/ecologia/
>>>>
>>>> PG ECO & BIODIV
>>>> http://www.rc.unesp.br/ib/ecologia/posbiodiversidade/index.php
>>>>
>>>> CV
>>>> http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4792988H6&mostrarNroCitacoesISI=true&mostrarNroCitacoesScopus=true
>>>>
>>>> Google citations http://scholar.google.com/citations?user=OWX_2eAAAAAJ
>>>
>>
>>
>> --
>> Miltinho - mcr at rc.unesp.br
>> Laboratório de Ecologia Espacial e Conservação - LEEC
>> Depto de Ecologia - UNESP - Rio Claro
>> Av. 24A, 1515- Bela Vista
>> 13506-900 Rio Claro, SP, Brasil
>>
>> Fone: +55 19 3526-9647 (office)  19 3526-9680 (lab)
>> Cel: 19 9853-3220 / 19 9853-5430
>>
>> Depto Ecologia http://www.rc.unesp.br/ib/ecologia/
>>
>> PG ECO & BIODIV http://www.rc.unesp.br/ib/ecologia/posbiodiversidade/index.php
>>
>> CV http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4792988H6&mostrarNroCitacoesISI=true&mostrarNroCitacoesScopus=true
>>
>> Google citations http://scholar.google.com/citations?user=OWX_2eAAAAAJ