[jira] [Created] (SPARK-7194) Vectors factors method for sparse vectors should accept the output of zipWithIndex

["Juliet Hougland (JIRA)" <ji...@apache.org>]

Juliet Hougland created SPARK-7194:
--------------------------------------

             Summary: Vectors factors method for sparse vectors should accept the output of zipWithIndex
                 Key: SPARK-7194
                 URL: https://issues.apache.org/jira/browse/SPARK-7194
             Project: Spark
          Issue Type: Improvement
            Reporter: Juliet Hougland


Let's say we have an RDD of Array[Double] where zero values are explictly recorded. Ie (0.0, 0.0, 3.2, 0.0...) If we want to transform this into an RDD of sparse vectors, we currently have to:

arr_doubles.map{ array =>
   val indexElem: Seq[(Int, Double)] = array.zipWithIndex.filter(tuple =>  tuple._1 != 0.0).map(tuple => (tuple._2, tuple._1))
Vectors.sparse(arrray.length, indexElem)
}

Notice that there is a map step at the end to switch the order of the index and the element value after .zipWithIndex. There should be a factory method on the Vectors class that allows you to avoid this flipping of tuple elements when using zipWithIndex.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org