Re: [igraph] basic question on selecting a vertex

[Simone Gabbriellini]

Gabor, Charles,

thanks for the hints! they both work fine!

best,
Simone

2012/3/20 Charles Novaes de Santana <address@hidden>:
> hehehe Exactly! Thanks for the correction, Gábor! :)
>
> But I am impressed with the way you suggested before! Igraph 0.6
> really simplify our life a lot!!
>
> Charles
>
> On Tue, Mar 20, 2012 at 7:22 PM, Gábor Csárdi <address@hidden> wrote:
>> On Tue, Mar 20, 2012 at 2:20 PM, Charles Novaes de Santana
>> <address@hidden> wrote:
>>> Hi Simone,
>>>
>>> Considering you have the names of your vertices in a variable named
>>> "vertices", in a very straightforward way you could do:
>>>
>>> v1<-which(vertices=="this");
>>> v2<-which(vertices=="that");
>>> g<-add.edges(g,c(v1,v2));
>>
>> This is good, except that you need to subtract one, because vertices
>> are numbered from zero.
>>
>> G.
>>
>>> So, the R function you are looking for is called "which".
>>>
>>> Surely there are other (more elegant) ways to do it, but that is the
>>> one I remember now.
>>>
>>> All the best,
>>>
>>> Charles
>>>
>>> On Tue, Mar 20, 2012 at 6:59 PM, Simone Gabbriellini
>>> <address@hidden> wrote:
>>>> Dear List,
>>>>
>>>> sorry for this very basic question, but I am trying to select a vertex
>>>> based on the value of an attribute. I forgot the R syntax, and I got
>>>> lost trying to pick it up again...
>>>>
>>>> I would like to create an edge between two nodes for which I only know
>>>> the value of the attribute, like:
>>>>
>>>> add.edges(g, c( the-ID-of-vertex-with-name=="this",
>>>> the-ID-of-vertex-with-name=="that"))
>>>>
>>>> can you please advice?
>>>>
>>>> Best,
>>>> Simone
>>>>
>>>> --
>>>> Dr. Simone Gabbriellini
>>>>
>>>> DigitalBrains srl
>>>> Amministratore
>>>>
>>>> mobile: +39 3403975626
>>>> mail: address@hidden
>>>>
>>>> _______________________________________________
>>>> igraph-help mailing list
>>>> address@hidden
>>>> https://lists.nongnu.org/mailman/listinfo/igraph-help
>>>
>>>
>>>
>>> --
>>> Um axé! :)
>>>
>>> --
>>> Charles Novaes de Santana
>>> http://www.imedea.uib-csic.es/~charles
>>> PhD student - Global Change
>>> Laboratorio Internacional de Cambio Global
>>> Department of Global Change Research
>>> Instituto Mediterráneo de Estudios Avanzados(CSIC/UIB)
>>> Calle Miquel Marques 21, 07190
>>> Esporles - Islas Baleares - España
>>>
>>> Office phone - +34 971 610 896
>>> Cell phone - +34 660 207 940
>>>
>>> _______________________________________________
>>> igraph-help mailing list
>>> address@hidden
>>> https://lists.nongnu.org/mailman/listinfo/igraph-help
>>
>>
>>
>> --
>> Gabor Csardi <address@hidden>     MTA KFKI RMKI
>>
>> _______________________________________________
>> igraph-help mailing list
>> address@hidden
>> https://lists.nongnu.org/mailman/listinfo/igraph-help
>
>
>
> --
> Um axé! :)
>
> --
> Charles Novaes de Santana
> http://www.imedea.uib-csic.es/~charles
> PhD student - Global Change
> Laboratorio Internacional de Cambio Global
> Department of Global Change Research
> Instituto Mediterráneo de Estudios Avanzados(CSIC/UIB)
> Calle Miquel Marques 21, 07190
> Esporles - Islas Baleares - España
>
> Office phone - +34 971 610 896
> Cell phone - +34 660 207 940
>
> _______________________________________________
> igraph-help mailing list
> address@hidden
> https://lists.nongnu.org/mailman/listinfo/igraph-help



-- 
Dr. Simone Gabbriellini

DigitalBrains srl
Amministratore
Head R&D

mobile: +39 3403975626
mail: address@hidden