Converting RDD[org.apache.spark.sql.Row] to RDD[org.apache.spark.mllib.linalg.Vector]

Question

I am relatively new to Spark and Scala.

I am starting with the following dataframe (single column made out of a dense Vector of Doubles):

scala> v         


        

Answer 1

import org.apache.spark.mllib.linalg.Vectors

scaledDataOnly
   .rdd
   .map{
      row => Vectors.dense(row.getAs[Seq[Double]]("features").toArray)
     }

Answer 2

Just found out:

val scaledDataOnly_rdd = scaledDataOnly_pruned.map{x:Row => x.getAs[Vector](0)}

Answer 3

EDIT: use more sophisticated way to interpret fields in Row.

This is worked for me

val featureVectors = features.map(row => {
  Vectors.dense(row.toSeq.toArray.map({
    case s: String => s.toDouble
    case l: Long => l.toDouble
    case _ => 0.0
  }))
})

features is a DataFrame of spark SQL.