Hi Flavio, I'm not quite familiar with RDF or sparql, so not all of your code is clear to me.
Your first TODO is "compute subgraph for Person". Is "Person" a vertex id in your graph? A vertex value? And by "subgraph of Person", do you mean all the vertices that can be reached starting from this node and following the graph edges? -Vasia. On 14 April 2015 at 10:37, Flavio Pompermaier <pomperma...@okkam.it> wrote: > Hi to all, > I made a simple RDF Gelly test and I shared it on my github repo at > https://github.com/fpompermaier/rdf-gelly-test. > I basically setup the Gelly stuff but I can't proceed and compute the > drafted TODOs. > Could someone help me and implementing them..? > I think this could become a nice example of how Gelly could help in > handling RDF graphs :) > > Best, > Flavio > > On Mon, Mar 23, 2015 at 10:41 AM, Flavio Pompermaier <pomperma...@okkam.it > > > wrote: > > > Thanks Vasiliki, > > when I'll find the time I'll try to make a quick prototype using the > > pointers you suggested! > > > > Thanks for the support, > > Flavio > > > > On Mon, Mar 23, 2015 at 10:31 AM, Vasiliki Kalavri < > > vasilikikala...@gmail.com> wrote: > > > >> Hi Flavio, > >> > >> I'm not familiar with JSON-LD, but as far as I understand, you want to > >> generate some trees from selected root nodes. > >> > >> Once you have created the Graph as Andra describes above, you can first > >> filter out the edges that are of no interest to you, using > filterOnEdges. > >> There is a description of how edge filtering works in the Gelly docs > [1]. > >> Then, you could use a vertex-centric iteration and propagate a message > >> from > >> the selected root node to the neighbors recursively, until you have the > >> tree. > >> > >> In the vertex-centric model, you program from the perspective of a > vertex > >> in the graph. You basically need to define what each vertex does within > >> each iteration (superstep). In Gelly this boils down to two things: > >> (a) what messages this vertex will send to its neighbors and > >> (b) how a vertex will update its value using the received messages. > >> > >> This is also described in the Gelly docs [2]. > >> Also, take a look at the Gelly library [3]. The library methods are > >> implemented using this model and should give you an idea. > >> > >> In your case, you will probably need to simply propagate one message > from > >> the root node and gather the newly discovered neighbors in each > superstep. > >> > >> I hope this helps! Let us know if you have further questions! > >> > >> -Vasia. > >> > >> [1]: > >> > >> > http://ci.apache.org/projects/flink/flink-docs-master/gelly_guide.html#graph-transformations > >> > >> [2]: > >> > >> > http://ci.apache.org/projects/flink/flink-docs-master/gelly_guide.html#vertex-centric-iterations > >> > >> [3]: > >> > >> > http://github.com/apache/flink/tree/master/flink-staging/flink-gelly/src/main/java/orgThehveflink/graph/library > >> > > > > > > >
