如何在Scala Spark中将稀疏矢量转换为密集？

Question

I have a sparse vector:

(453,[0,4,11,16,39,56,109],[1.0,1.0,1.0,1.0,1.0,1.0,1.0])

and I need to convert it into dense vector (should be able to see all 453 values).

How to do that in Scala Spark?

Answer 1

It can be done by using SparseVector 's toDense method:

val sv = Vectors.sparse(5, Array(0, 3), Array(1.5, -1.5))
sv.toDense
// res0: org.apache.spark.mllib.linalg.DenseVector = [1.5,0.0,0.0,-1.5,0.0]