Hi Lydia, an iteration aggregator combines all aggregates globally once per superstep and makes them available in the *next* superstep. Within each scatter-gather iteration, one MessagingFunction (scatter phase) and one VertexUpdateFunction (gather phase) are executed. Thus, if you set an aggregate value within one of those, the value will be available in the next superstep. You can retrieve it calling the getPreviousIterationAggregate() method. Let me know if that clears things up!
-Vasia. On 13 May 2016 at 08:57, Lydia Ickler <ickle...@googlemail.com> wrote: > Hi Vasia, > > yes, but only independently within each Function or not? > > If I set the aggregator in VertexUpdateFunction then the newly set value > is not visible in the MessageFunction. > Or am I doing something wrong? I would like to have a shared aggregator > to normalize vertices. > > > Am 13.05.2016 um 08:04 schrieb Vasiliki Kalavri <vasilikikala...@gmail.com > >: > > Hi Lydia, > > registered aggregators through the ScatterGatherConfiguration are > accessible both in the VertexUpdateFunction and in the MessageFunction. > > Cheers, > -Vasia. > > On 12 May 2016 at 20:08, Lydia Ickler <ickle...@googlemail.com> wrote: > >> Hi, >> >> I have a question regarding the Aggregators of a Scatter-Gather >> Iteration. >> Is it possible to have a global aggregator that is accessible in >> VertexUpdateFunction() >> and MessagingFunction() at the same time? >> >> Thanks in advance, >> Lydia >> > > >
