spark-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Robin East <robin.e...@xense.co.uk>
Subject Re: GraphX path traversal
Date Tue, 03 Mar 2015 16:32:35 GMT
What about the following which can be run in spark shell:

import org.apache.spark._
import org.apache.spark.graphx._
import org.apache.spark.rdd.RDD

val vertexlist = Array((1L,"One"), (2L,"Two"), (3L,"Three"), (4L,"Four"),(5L,"Five"),(6L,"Six"))
val edgelist = Array(Edge(6,5,"6 to 5"),Edge(5,4,"5 to 4"),Edge(4,3,"4 to 3"), Edge(3,2,"3
to 2"), Edge(2,1,"2 to 1"))
val vertices: RDD[(VertexId, String)] =  sc.parallelize(vertexlist)
val edges = sc.parallelize(edgelist)
val graph = Graph(vertices, edges)

val triplets = graph.triplets

triplets.foreach(t => println(s"parent for ${t.dstId} is ${t.srcId}"))

It doesn’t set vertex 6 to have parent 6 but you get the idea.

It doesn’t use Pregel but that sounds like overkill for what you are trying to achieve.

Does that answer your question or were you after something different?



> On 3 Mar 2015, at 15:12, Madabhattula Rajesh Kumar <mrajaforu@gmail.com> wrote:
> 
> Hi Robin,
> 
> Thank you for your response. Please find below my question. I have a below edge file
> 
> Source Vertex	Destination Vertex
> 1	2
> 2	3
> 3	4
> 4	5
> 5	6
> 6	6
> 
> In this graph 1st vertex is connected to 2nd vertex, 2nd Vertex is connected to 3rd vertex,.....
6th vertex is connected to 6th vertex. So 6th vertex is a root node. Please find below graph
> 
> <image.png>
> In this graph, How can I compute the 1st vertex parents like 2,3,4,5,6. Similarly 2nd
vertex parents like 3,4,5,6 .... 6th vertex parent like 6 because this is the root node.
> 
> I'm planning to use pergel API but I'm not able to define messages and vertex program
in that API. Could you please help me on this.
> 
> Please let me know if you need more information.
> 
> Regards,
> Rajesh
> 
> 
> On Tue, Mar 3, 2015 at 8:15 PM, Robin East <robin.east@xense.co.uk <mailto:robin.east@xense.co.uk>>
wrote:
> Rajesh
> 
> I'm not sure if I can help you, however I don't even understand the question. Could you
restate what you are trying to do.
> 
> Sent from my iPhone
> 
> On 2 Mar 2015, at 11:17, Madabhattula Rajesh Kumar <mrajaforu@gmail.com <mailto:mrajaforu@gmail.com>>
wrote:
> 
>> Hi,
>> 
>> I have a below edge list. How to find the parents path for every vertex?
>> 
>> Example :
>> 
>> Vertex 1 path : 2, 3, 4, 5, 6
>> Vertex 2 path : 3, 4, 5, 6
>> Vertex 3 path : 4,5,6
>> vertex 4 path : 5,6
>> vertex 5 path : 6
>> 
>> Could you please let me know how to do this? (or) Any suggestion
>> 
>> Source Vertex	Destination Vertex
>> 1	2
>> 2	3
>> 3	4
>> 4	5
>> 5	6
>> 
>> Regards,
>> Rajesh
> 


Mime
View raw message