[GRASS-user] Using v.distance between two identical layers...

[Nicolas DEVAUX]

Hamish a écrit :
> devaux wrote:
>   
>> do you know if it's possible to use v.distance command when
>> "for" and "to" layers are
>> the same layer ?
>> I have a layer describing ecological areas of interest and
>> I want to qualify spatial
>> relation between all patches. I want to identify and
>> calculate shortest relation between
>> all my patches boundaries.
>>
>> How can I do as v.distance command doesn't have any option
>> like : eliminate identical
>> objects from the "from" and "to" layer ?
>>
>> I'd like to use this particular command because of the
>> option that create lines between
>> nearest objects.
>>     
>
>
> use g.copy or v.extract as a first step to separate/duplicate the
> features?     
>
> Hamish
g.copy will duplicate features, but will not avoid v.distance to search 
distance between "from" layer feature to all features except itself in 
the "to" layer. Or do you mean to do a script that isolate iteratively 
each feature from the cover time by time (it might be very long as I 
have a lot of features...) and use v.distance as many time as features 
number ?

Nicolas

-- 
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Nicolas DEVAUX
Laboratoire d'étude des Interactions entre Sol, Agrosystème et Hydrosystème
UMR LISAH AgroM-INRA-IRD
Bat. 24
place Viala
34060 Montpellier cedex 1

tél : +33 0(4) 99 61 25 45
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email: devaux at supagro.inra.fr
http://sol.ensam.inra.fr/lisah/
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