Here’s a way of creating sparse vectors in MLLib: import org.apache.spark.mllib.linalg.Vectors import org.apache.spark.rdd.RDD
val rdd = sc.textFile("A.txt").map(line => line.split(",")). map(ary => (ary(0).toInt, ary(1).toInt, ary(2).toDouble)) val pairRdd: RDD[(Int, (Int, Int, Double))] = rdd.map(el => (el._1, el)) val create = (first: (Int, Int, Double)) => (Array(first._2), Array(first._3)) val combine = (head: (Array[Int], Array[Double]), tail: (Int, Int, Double)) => (head._1 :+ tail._2, head._2 :+ tail._3) val merge = (a: (Array[Int], Array[Double]), b: (Array[Int], Array[Double])) => (a._1 ++ b._1, a._2 ++ b._2) val A = pairRdd.combineByKey(create,combine,merge).map(el => Vectors.sparse(3,el._2._1,el._2._2)) If you have a separate file of b’s then you would need to manipulate this slightly to join the b’s to the A RDD and then create LabeledPoints. I guess there is a way of doing this using the newer ML interfaces but it’s not particularly obvious to me how. One point: In the example you give the b’s are exactly the same as col 2 in the A matrix. I presume this is just a quick hacked together example because that would give a trivial result. ------------------------------------------------------------------------------- Robin East Spark GraphX in Action Michael Malak and Robin East Manning Publications Co. http://www.manning.com/books/spark-graphx-in-action <http://www.manning.com/books/spark-graphx-in-action> > On 3 Nov 2016, at 18:12, im281 [via Apache Spark User List] > <ml-node+s1001560n28008...@n3.nabble.com> wrote: > > I would like to use it. But how do I do the following > 1) Read sparse data (from text or database) > 2) pass the sparse data to the linearRegression class? > > For example: > > Sparse matrix A > row, column, value > 0,0,.42 > 0,1,.28 > 0,2,.89 > 1,0,.83 > 1,1,.34 > 1,2,.42 > 2,0,.23 > 3,0,.42 > 3,1,.98 > 3,2,.88 > 4,0,.23 > 4,1,.36 > 4,2,.97 > > Sparse vector b > row, column, value > 0,2,.89 > 1,2,.42 > 3,2,.88 > 4,2,.97 > > Solve Ax = b??? > > > > If you reply to this email, your message will be added to the discussion > below: > http://apache-spark-user-list.1001560.n3.nabble.com/mLIb-solving-linear-regression-with-sparse-inputs-tp28006p28008.html > > <http://apache-spark-user-list.1001560.n3.nabble.com/mLIb-solving-linear-regression-with-sparse-inputs-tp28006p28008.html> > To start a new topic under Apache Spark User List, email > ml-node+s1001560n1...@n3.nabble.com > To unsubscribe from Apache Spark User List, click here > <http://apache-spark-user-list.1001560.n3.nabble.com/template/NamlServlet.jtp?macro=unsubscribe_by_code&node=1&code=Um9iaW4uZWFzdEB4ZW5zZS5jby51a3wxfDIzMzQzMDUyNg==>. > NAML > <http://apache-spark-user-list.1001560.n3.nabble.com/template/NamlServlet.jtp?macro=macro_viewer&id=instant_html%21nabble%3Aemail.naml&base=nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.view.web.template.NodeNamespace&breadcrumbs=notify_subscribers%21nabble%3Aemail.naml-instant_emails%21nabble%3Aemail.naml-send_instant_email%21nabble%3Aemail.naml> ----- Robin East Spark GraphX in Action Michael Malak and Robin East Manning Publications Co. http://www.manning.com/books/spark-graphx-in-action -- View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/mLIb-solving-linear-regression-with-sparse-inputs-tp28006p28027.html Sent from the Apache Spark User List mailing list archive at Nabble.com.