I leave here the shortest path algorithm that i'm using (maybe it's
necesary for a better understanding of my question), it's an adaptation of
the Original Shortest Path Example of Giraph:
@Algorithm(name = "Shortest paths", description = "Finds all shortest paths
from a selected vertex")
public class SimpleShortestPathComputationMio extends
BasicComputation<Text, DoubleWritable, DoubleWritable,
DoubleWritable> {
/** The shortest paths id */
public static final LongConfOption SOURCE_ID = new LongConfOption(
"SimpleShortestPathsVertex.sourceId", 1, "The shortest paths
id");
/** Class logger */
private static final Logger LOG = Logger
.getLogger(SimpleShortestPathComputationMio.class);
/**
* Is this vertex the source id?
*
* @param vertex
* Vertex
* @return True if the source id
*/
private boolean isSource(Vertex<Text, ?, ?> vertex) {
return vertex.getId().equals(SOURCE_ID.get(getConf()));
}
@Override
public void compute(Vertex<Text, DoubleWritable, DoubleWritable> vertex,
Iterable<DoubleWritable> messages) throws IOException {
if (getSuperstep() == 0) {
vertex.setValue(new DoubleWritable(Double.MAX_VALUE));
}
Double minDist = isSource(vertex) ? Double.valueOf(0)
: Double.MAX_VALUE;
for (DoubleWritable message : messages) {
minDist = Math.min(minDist, message.get());
}
if (LOG.isDebugEnabled()) {
LOG.debug("Vertex " + vertex.getId() + " got minDist = " +
minDist
+ " vertex value = " + vertex.getValue());
}
if (minDist < vertex.getValue().get()) {
vertex.setValue(new DoubleWritable(minDist));
for (Edge<Text, DoubleWritable> edge : vertex.getEdges()) {
Double distance = minDist + edge.getValue().get();
if (LOG.isDebugEnabled()) {
LOG.debug("Vertex " + vertex.getId() + " sent to "
+ edge.getTargetVertexId() + " = " + distance);
}
sendMessage(edge.getTargetVertexId(), new DoubleWritable(
distance));
}
}
vertex.voteToHalt();
}
}
2015-07-29 23:11 GMT-03:00 José Luis Larroque <[email protected]>:
> Hi everyone, i'm Jose from Argentina, and i'm working with Giraph for my
> thesis. I'm stuck in the same point weeks ago, so finally i decided to come
> and ask for help !
>
> I have a multinode giraph cluster working properly in my PC. I executed
> the SimpleShortestPathExample from Giraph and was executed fine.
>
> This algorithm was ran with this file (tiny_graph.txt):
>
> [0,0,[[1,1],[3,3]]]
> [1,0,[[0,1],[2,2],[3,1]]]
> [2,0,[[1,2],[4,4]]]
> [3,0,[[0,3],[1,1],[4,4]]]
> [4,0,[[3,4],[2,4]]]
>
> This file has the following input format:
>
> [source_id,source_value,[[dest_id, edge_value],...]]
>
> Now, I’m trying to execute this same algorithm, in this same cluster, but
> with an input file different from the original. My own file is like this:
>
> [Portada,0,[[Sugerencias para la cita del día,1]]]
> [Proverbios españoles,0,[]]
> [Neil
> Armstrong,0,[[Luna,1][ideal,1][verdad,1][Categoria:Ingenieros,2,[Categoria:Estadounidenses,2][Categoria:Astronautas,2]]]
> [Categoria:Ingenieros,1,[[Neil Armstrong,2]]]
> [Categoria:Estadounidenses,1,[[Neil Armstrong,2]]]
> [Categoria:Astronautas,1,[[Neil Armstrong,2]]]
>
> It's very similar to the original, but the id's are String and the vertex
> and edges values are Long. My question it's which VertexInputFormat should
> i use for this kind of format, because i already try with
> org.apache.giraph.io.formats.JsonLongDoubleFloatDoubleVertexInputFormat
> and
> org.apache.giraph.io.formats.TextDoubleDoubleAdjacencyListVertexInputFormat
> and i couldn't get this working.
>
> With this problem solved, i could adapt the original shortest path example
> algorithm and let it work for my file, but until i get a solution for this
> i can't reach to that point.
>
> If this format it's not a good decision, i could adapt it maybe, but i
> don't know which it's my best option, my knowledge from Vertex Text Input
> and Output Format in giraph it's really bad, that's why i'me here asking
> for some advice.
>
>
> Thanks in advance!!
>
>
> Jose
>
