CGAL users discussion list

[Laurent Le Guillou <>]

Thanks a lot!

I will try your code and let you know what I got.

Cheers,

Laurent


Andreas Fabri a écrit :
> Laurent Le Guillou wrote:
>> Hello,
>>
>> With CGAL, is there a way to enumerate (with an iterator
>> or something) the neighboors of a vertex : for instance all the
>> first neighboors ("order 1" neighboors), the second neighboors
>> (neighboor of a neighboor, "order 2" neighboors), the third
>> neighboors ("order 3"), and so on, but without enumerating the same
>> vertex twice. I am a physicist, without a very deep knowledge of
>> graph-related mathematics; I searched in graph-literature but did
>> not found any simple algorithm. I need something quite fast as I
>> want to select all the neighboors of a given vertex of "order" less
>> than a fixed k, and I need to do this for all vertices, in order
>> to compute local physical properties (a "local plane" and other
>> mechanical properties).
> 
> Note that the code I posted does it for one vertex
> and exhaustively.
> So you have to run it for each vertex and have a
> distance recorder that stops when k is reached.
> 
> andreas
> 
>>
>> Thanks a lot if someone could give me a hint on how to do this
>> in an efficient way (I may of course walk across the whole
>> polyhedron data structure several times, but my polyhedrons
>> have tens of thousands points...).
>>
>> Cheers,
>>
>> Laurent
>>
>> -----------------------------------------------------------------------
>>   Laurent LE GUILLOU                      Tel +33 1 44 27 39 93
>>   
>> 
>>                       Fax +33 1 44 27 46 38
>>   
>> 
>>               GSM +33 6 20 05 75 22
>>
>>   LPNHE - Université Paris 6
>>   Bureau 412 - Tour 33 RdC
>>   Campus de Jussieu
>>   4 place Jussieu
>>   75252 Paris Cedex 05


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-----------------------------------------------------------------------
  Laurent LE GUILLOU                      Tel +33 1 44 27 39 93
  

                      Fax +33 1 44 27 46 38
  

              GSM +33 6 20 05 75 22

  LPNHE - Université Paris 6
  Bureau 412 - Tour 33 RdC
  Campus de Jussieu
  4 place Jussieu
  75252 Paris Cedex 05