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From Lukas Nalezenec <lukas.naleze...@firma.seznam.cz>
Subject Re: concept of vertex in giraph
Date Fri, 25 Jul 2014 17:04:23 GMT
Hi
IMHO third way, overriding method combine in own Partition is best.
Lukas

On 25.7.2014 18:47, Schweiger, Tom wrote:
> Edges "combine" differently than vertexes.
>
> By default, each edge you read is added to the adjacency set of the 
> source vertex (all edges are directed in Giraph, if you had not 
> realized that yet).  So if you read multiple edge for the same source 
> -> target, they will all be represented in the source vertex's edges.
>
> If you actually need to combine edges there are two way to go about it.
>
> 1) (easy but unelegant) deal with the fact in your compute
>
> 2) (more involved but efficient) write your own OutEdges class, unless 
> one already exists that does what you need.
>
>
> ------------------------------------------------------------------------
> *From:* Carmen Manzulli [carmenmanzulli@gmail.com]
> *Sent:* Friday, July 25, 2014 1:56 AM
> *To:* user@giraph.apache.org
> *Subject:* Re: concept of vertex in giraph
>
> ah ok, thanksa lot!...so is the same for edgevalues and 
> targetvertexids??? i need to use combiners, can you show me where can 
> i read more information about?
>
>
> 2014-07-25 10:52 GMT+02:00 Lukas Nalezenec 
> <lukas.nalezenec@firma.seznam.cz 
> <mailto:lukas.nalezenec@firma.seznam.cz>>:
>
>     Hi,
>     Afaik vertex ids must be unique but you can combine vertexes with
>     same ID to one using VertexValueCombiner.
>
>     Lukas
>
>
>     On 25.7.2014 10:33, Carmen Manzulli wrote:
>>      Hi experts,
>>     i would like to ask you if , in the graph rapresentation, every
>>     time a vertexId is reapeated, would giraph consider just one time
>>     that vertexId?
>>
>>     for example:
>>
>>     Carmen (vertexId) 24 (vertex value) .....
>>     Carmen (vertexId) 1,60 m (vertex value)...
>>
>>     does it became
>>
>>     Carmen -->24
>>                 -->1,60
>>
>>     from a point of view conceptual?
>
>


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