GraphX-Spark: error graph.vertices.filter

Question

I am new in scala and spark-graphx. This is a method that I've written to extract the vertex that has min score value

def getMinScoreVertex(graph: Graph[(Int,Float,Float,Float,String),Float]):Float={
var minValue:Float=Float.PositiveInfinity
var LowestScoreValue=graph.vertices.filter { case (id,(_,_,_,Score,_)) => Score < minValue}
 return LowestScoreValue  }

I get the following error:

Error:(15, 62) constructor cannot be instantiated to expected type;
 found   : (T1, T2, T3, T4, T5)
 required: (org.apache.spark.graphx.VertexId, (Int, Float, Float, Float, String))
    (which expands to)  (Long, (Int, Float, Float, Float, String))
    var LowestScoreValue=graph.vertices.filter { case (_,_,_,Score,_) => Score < minValue}
Error:(15, 69) not found: value Score
    var LowestScoreValue=graph.vertices.filter { case (_,_,_,Score,_) => Score < minValue}
Error:(15, 82) not found: value Score
    var LowestScoreValue=graph.vertices.filter { case (_,_,_,Score,_) => Score < minValue}

Any ideas?? Thanks

Use `case` correctly. `case (_,_,_,s: Score,_) => s < minValue` — NaHeon, Oct 23 '16 at 10:27

score 0 · Accepted Answer · edited May 23 '17 at 12:16

0

At the commend I made a mistake, thinking Score is type. Most of time if you do pattern matching, it's safe to use lower-case letters. (lowercased variables in pattern matching)

val filterResult = graph.vertices.filter {
    case (_, (_, _, _, score, _)) => score < minValue
}

This will not give compilation error.

One more thing is filter is not the right choice to select the minimum choice. It'll just filter VertexRDD which has score less than minValue and will return list.

edited May 23 '17 at 12:16

Community

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answered Oct 23 '16 at 12:45

NaHeon

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Thank you for your answer. Always the same compilation error. – imen Oct 23 '16 at 13:06
Type mismatch expected (graphx.VertexId,(Int,Float,Float,Float,String))=>Boolean , actual: (graphx.VertexId,(Int,Float,Float,Float,String))=>Any – imen Oct 23 '16 at 13:08
@imen My worksheet is clean. Is it at `filterResult`? – NaHeon Oct 23 '16 at 13:13
@imen nice :) Could you choose the answer please if I may? – NaHeon Oct 24 '16 at 00:41

GraphX-Spark: error graph.vertices.filter

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