SPARK-1462: Examples of ML algorithms are using deprecated APIs

This will also fix SPARK-1464: Update MLLib Examples to Use Breeze.

Author: Sandeep <sandeep@techaddict.me>

Closes #416 from techaddict/1462 and squashes the following commits:

a43638e [Sandeep] Some Style Changes
3ce69c3 [Sandeep] Fix Ordering and Naming of Imports in Examples
6c7e543 [Sandeep] SPARK-1462: Examples of ML algorithms are using deprecated APIs

20 files changed, 100 insertions, 66 deletions

diff --git a/examples/src/main/scala/org/apache/spark/examples/CassandraCQLTest.scala b/examples/src/main/scala/org/apache/spark/examples/CassandraCQLTest.scala
index 1f8d7cb599..4e787240e9 100644
--- a/examples/src/main/scala/org/apache/spark/examples/CassandraCQLTest.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/CassandraCQLTest.scala
@@ -18,15 +18,18 @@
 package org.apache.spark.examples
 
 import java.nio.ByteBuffer
+
 import scala.collection.JavaConversions._
 import scala.collection.mutable.ListBuffer
 import scala.collection.immutable.Map
+
 import org.apache.cassandra.hadoop.ConfigHelper
 import org.apache.cassandra.hadoop.cql3.CqlPagingInputFormat
 import org.apache.cassandra.hadoop.cql3.CqlConfigHelper
 import org.apache.cassandra.hadoop.cql3.CqlOutputFormat
 import org.apache.cassandra.utils.ByteBufferUtil
 import org.apache.hadoop.mapreduce.Job
+
 import org.apache.spark.SparkContext
 import org.apache.spark.SparkContext._
 
diff --git a/examples/src/main/scala/org/apache/spark/examples/CassandraTest.scala b/examples/src/main/scala/org/apache/spark/examples/CassandraTest.scala
index 3e3a3b2d50..ed5d2f9e46 100644
--- a/examples/src/main/scala/org/apache/spark/examples/CassandraTest.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/CassandraTest.scala
@@ -17,19 +17,21 @@
 
 package org.apache.spark.examples
 
-import org.apache.hadoop.mapreduce.Job
+import java.nio.ByteBuffer
+import java.util.SortedMap
+
+import scala.collection.JavaConversions._
+
+import org.apache.cassandra.db.IColumn
 import org.apache.cassandra.hadoop.ColumnFamilyOutputFormat
 import org.apache.cassandra.hadoop.ConfigHelper
 import org.apache.cassandra.hadoop.ColumnFamilyInputFormat
 import org.apache.cassandra.thrift._
-import org.apache.spark.SparkContext
-import org.apache.spark.SparkContext._
-import java.nio.ByteBuffer
-import java.util.SortedMap
-import org.apache.cassandra.db.IColumn
 import org.apache.cassandra.utils.ByteBufferUtil
-import scala.collection.JavaConversions._
+import org.apache.hadoop.mapreduce.Job
 
+import org.apache.spark.SparkContext
+import org.apache.spark.SparkContext._
 
 /*
  * This example demonstrates using Spark with Cassandra with the New Hadoop API and Cassandra
diff --git a/examples/src/main/scala/org/apache/spark/examples/GroupByTest.scala b/examples/src/main/scala/org/apache/spark/examples/GroupByTest.scala
index 29114c6dab..2b7ecdc991 100644
--- a/examples/src/main/scala/org/apache/spark/examples/GroupByTest.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/GroupByTest.scala
@@ -17,9 +17,10 @@
 
 package org.apache.spark.examples
 
+import java.util.Random
+
 import org.apache.spark.SparkContext
 import org.apache.spark.SparkContext._
-import java.util.Random
 
 object GroupByTest {
   def main(args: Array[String]) {
diff --git a/examples/src/main/scala/org/apache/spark/examples/HBaseTest.scala b/examples/src/main/scala/org/apache/spark/examples/HBaseTest.scala
index 700121d16d..cbf78e8e9e 100644
--- a/examples/src/main/scala/org/apache/spark/examples/HBaseTest.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/HBaseTest.scala
@@ -17,12 +17,13 @@
 
 package org.apache.spark.examples
 
-import org.apache.spark._
-import org.apache.spark.rdd.NewHadoopRDD
-import org.apache.hadoop.hbase.{HBaseConfiguration, HTableDescriptor}
 import org.apache.hadoop.hbase.client.HBaseAdmin
+import org.apache.hadoop.hbase.{HBaseConfiguration, HTableDescriptor}
 import org.apache.hadoop.hbase.mapreduce.TableInputFormat
 
+import org.apache.spark._
+import org.apache.spark.rdd.NewHadoopRDD
+
 object HBaseTest {
   def main(args: Array[String]) {
     val sc = new SparkContext(args(0), "HBaseTest",
diff --git a/examples/src/main/scala/org/apache/spark/examples/LocalALS.scala b/examples/src/main/scala/org/apache/spark/examples/LocalALS.scala
index 37ad4bd099..658f73d96a 100644
--- a/examples/src/main/scala/org/apache/spark/examples/LocalALS.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/LocalALS.scala
@@ -18,9 +18,10 @@
 package org.apache.spark.examples
 
 import scala.math.sqrt
-import cern.jet.math._
+
 import cern.colt.matrix._
 import cern.colt.matrix.linalg._
+import cern.jet.math._
 
 /**
  * Alternating least squares matrix factorization.
diff --git a/examples/src/main/scala/org/apache/spark/examples/LocalFileLR.scala b/examples/src/main/scala/org/apache/spark/examples/LocalFileLR.scala
index 737c444139..0ef3001ca4 100644
--- a/examples/src/main/scala/org/apache/spark/examples/LocalFileLR.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/LocalFileLR.scala
@@ -18,17 +18,18 @@
 package org.apache.spark.examples
 
 import java.util.Random
-import org.apache.spark.util.Vector
+
+import breeze.linalg.{Vector, DenseVector}
 
 object LocalFileLR {
   val D = 10   // Numer of dimensions
   val rand = new Random(42)
 
-  case class DataPoint(x: Vector, y: Double)
+  case class DataPoint(x: Vector[Double], y: Double)
 
   def parsePoint(line: String): DataPoint = {
     val nums = line.split(' ').map(_.toDouble)
-    DataPoint(new Vector(nums.slice(1, D + 1)), nums(0))
+    DataPoint(new DenseVector(nums.slice(1, D + 1)), nums(0))
   }
 
   def main(args: Array[String]) {
@@ -37,15 +38,15 @@ object LocalFileLR {
     val ITERATIONS = args(1).toInt
 
     // Initialize w to a random value
-    var w = Vector(D, _ => 2 * rand.nextDouble - 1)
+    var w = DenseVector.fill(D){2 * rand.nextDouble - 1}
     println("Initial w: " + w)
 
     for (i <- 1 to ITERATIONS) {
       println("On iteration " + i)
-      var gradient = Vector.zeros(D)
+      var gradient = DenseVector.zeros[Double](D)
       for (p <- points) {
-        val scale = (1 / (1 + math.exp(-p.y * (w dot p.x))) - 1) * p.y
-        gradient +=  scale * p.x
+        val scale = (1 / (1 + math.exp(-p.y * (w.dot(p.x)))) - 1) * p.y
+        gradient += p.x * scale
       }
       w -= gradient
     }
diff --git a/examples/src/main/scala/org/apache/spark/examples/LocalKMeans.scala b/examples/src/main/scala/org/apache/spark/examples/LocalKMeans.scala
index 3895675b3b..e33a1b336d 100644
--- a/examples/src/main/scala/org/apache/spark/examples/LocalKMeans.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/LocalKMeans.scala
@@ -18,11 +18,14 @@
 package org.apache.spark.examples
 
 import java.util.Random
-import org.apache.spark.util.Vector
-import org.apache.spark.SparkContext._
+
 import scala.collection.mutable.HashMap
 import scala.collection.mutable.HashSet
 
+import breeze.linalg.{Vector, DenseVector, squaredDistance}
+
+import org.apache.spark.SparkContext._
+
 /**
  * K-means clustering.
  */
@@ -36,19 +39,19 @@ object LocalKMeans {
 
   def generateData = {
     def generatePoint(i: Int) = {
-      Vector(D, _ => rand.nextDouble * R)
+      DenseVector.fill(D){rand.nextDouble * R}
     }
     Array.tabulate(N)(generatePoint)
   }
 
-  def closestPoint(p: Vector, centers: HashMap[Int, Vector]): Int = {
+  def closestPoint(p: Vector[Double], centers: HashMap[Int, Vector[Double]]): Int = {
     var index = 0
     var bestIndex = 0
     var closest = Double.PositiveInfinity
 
     for (i <- 1 to centers.size) {
       val vCurr = centers.get(i).get
-      val tempDist = p.squaredDist(vCurr)
+      val tempDist = squaredDistance(p, vCurr)
       if (tempDist < closest) {
         closest = tempDist
         bestIndex = i
@@ -60,8 +63,8 @@ object LocalKMeans {
 
   def main(args: Array[String]) {
     val data = generateData
-    var points = new HashSet[Vector]
-    var kPoints = new HashMap[Int, Vector]
+    var points = new HashSet[Vector[Double]]
+    var kPoints = new HashMap[Int, Vector[Double]]
     var tempDist = 1.0
 
     while (points.size < K) {
@@ -81,16 +84,17 @@ object LocalKMeans {
       var mappings = closest.groupBy[Int] (x => x._1)
 
       var pointStats = mappings.map { pair =>
-        pair._2.reduceLeft [(Int, (Vector, Int))] {
+        pair._2.reduceLeft [(Int, (Vector[Double], Int))] {
           case ((id1, (x1, y1)), (id2, (x2, y2))) => (id1, (x1 + x2, y1 + y2))
         }
       }
 
-      var newPoints = pointStats.map {mapping => (mapping._1, mapping._2._1/mapping._2._2)}
+      var newPoints = pointStats.map {mapping =>
+        (mapping._1, mapping._2._1 * (1.0 / mapping._2._2))}
 
       tempDist = 0.0
       for (mapping <- newPoints) {
-        tempDist += kPoints.get(mapping._1).get.squaredDist(mapping._2)
+        tempDist += squaredDistance(kPoints.get(mapping._1).get, mapping._2)
       }
 
       for (newP <- newPoints) {
diff --git a/examples/src/main/scala/org/apache/spark/examples/LocalLR.scala b/examples/src/main/scala/org/apache/spark/examples/LocalLR.scala
index cd4e9f1af0..385b48089d 100644
--- a/examples/src/main/scala/org/apache/spark/examples/LocalLR.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/LocalLR.scala
@@ -18,7 +18,8 @@
 package org.apache.spark.examples
 
 import java.util.Random
-import org.apache.spark.util.Vector
+
+import breeze.linalg.{Vector, DenseVector}
 
 /**
  * Logistic regression based classification.
@@ -30,12 +31,12 @@ object LocalLR {
   val ITERATIONS = 5
   val rand = new Random(42)
 
-  case class DataPoint(x: Vector, y: Double)
+  case class DataPoint(x: Vector[Double], y: Double)
 
   def generateData = {
     def generatePoint(i: Int) = {
       val y = if(i % 2 == 0) -1 else 1
-      val x = Vector(D, _ => rand.nextGaussian + y * R)
+      val x = DenseVector.fill(D){rand.nextGaussian + y * R}
       DataPoint(x, y)
     }
     Array.tabulate(N)(generatePoint)
@@ -45,15 +46,15 @@ object LocalLR {
     val data = generateData
 
     // Initialize w to a random value
-    var w = Vector(D, _ => 2 * rand.nextDouble - 1)
+    var w = DenseVector.fill(D){2 * rand.nextDouble - 1}
     println("Initial w: " + w)
 
     for (i <- 1 to ITERATIONS) {
       println("On iteration " + i)
-      var gradient = Vector.zeros(D)
+      var gradient = DenseVector.zeros[Double](D)
       for (p <- data) {
-        val scale = (1 / (1 + math.exp(-p.y * (w dot p.x))) - 1) * p.y
-        gradient +=  scale * p.x
+        val scale = (1 / (1 + math.exp(-p.y * (w.dot(p.x)))) - 1) * p.y
+        gradient +=  p.x * scale
       }
       w -= gradient
     }
diff --git a/examples/src/main/scala/org/apache/spark/examples/LocalPi.scala b/examples/src/main/scala/org/apache/spark/examples/LocalPi.scala
index bb7f22ec8d..ee6b3ee34a 100644
--- a/examples/src/main/scala/org/apache/spark/examples/LocalPi.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/LocalPi.scala
@@ -18,8 +18,9 @@
 package org.apache.spark.examples
 
 import scala.math.random
+
 import org.apache.spark._
-import SparkContext._
+import org.apache.spark.SparkContext._
 
 object LocalPi {
   def main(args: Array[String]) {
diff --git a/examples/src/main/scala/org/apache/spark/examples/LogQuery.scala b/examples/src/main/scala/org/apache/spark/examples/LogQuery.scala
index fcaba6bb4f..35758fa003 100644
--- a/examples/src/main/scala/org/apache/spark/examples/LogQuery.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/LogQuery.scala
@@ -19,6 +19,7 @@ package org.apache.spark.examples
 
 import org.apache.spark.SparkContext
 import org.apache.spark.SparkContext._
+
 /**
  * Executes a roll up-style query against Apache logs.
  */
diff --git a/examples/src/main/scala/org/apache/spark/examples/MultiBroadcastTest.scala b/examples/src/main/scala/org/apache/spark/examples/MultiBroadcastTest.scala
index 97321ab8f4..58f26f1e24 100644
--- a/examples/src/main/scala/org/apache/spark/examples/MultiBroadcastTest.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/MultiBroadcastTest.scala
@@ -17,8 +17,8 @@
 
 package org.apache.spark.examples
 
-import org.apache.spark.SparkContext
 import org.apache.spark.rdd.RDD
+import org.apache.spark.SparkContext
 
 object MultiBroadcastTest {
   def main(args: Array[String]) {
diff --git a/examples/src/main/scala/org/apache/spark/examples/SimpleSkewedGroupByTest.scala b/examples/src/main/scala/org/apache/spark/examples/SimpleSkewedGroupByTest.scala
index d05eedd31c..557a0c1841 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SimpleSkewedGroupByTest.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SimpleSkewedGroupByTest.scala
@@ -17,9 +17,10 @@
 
 package org.apache.spark.examples
 
+import java.util.Random
+
 import org.apache.spark.SparkContext
 import org.apache.spark.SparkContext._
-import java.util.Random
 
 object SimpleSkewedGroupByTest {
   def main(args: Array[String]) {
diff --git a/examples/src/main/scala/org/apache/spark/examples/SkewedGroupByTest.scala b/examples/src/main/scala/org/apache/spark/examples/SkewedGroupByTest.scala
index fd9f043247..05a74725b8 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SkewedGroupByTest.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SkewedGroupByTest.scala
@@ -17,9 +17,10 @@
 
 package org.apache.spark.examples
 
+import java.util.Random
+
 import org.apache.spark.SparkContext
 import org.apache.spark.SparkContext._
-import java.util.Random
 
 object SkewedGroupByTest {
   def main(args: Array[String]) {
diff --git a/examples/src/main/scala/org/apache/spark/examples/SparkALS.scala b/examples/src/main/scala/org/apache/spark/examples/SparkALS.scala
index 68f151a2c4..191c82fd91 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SparkALS.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SparkALS.scala
@@ -18,9 +18,11 @@
 package org.apache.spark.examples
 
 import scala.math.sqrt
-import cern.jet.math._
+
 import cern.colt.matrix._
 import cern.colt.matrix.linalg._
+import cern.jet.math._
+
 import org.apache.spark._
 
 /**
diff --git a/examples/src/main/scala/org/apache/spark/examples/SparkHdfsLR.scala b/examples/src/main/scala/org/apache/spark/examples/SparkHdfsLR.scala
index d8de8745c1..fd63ba3dbc 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SparkHdfsLR.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SparkHdfsLR.scala
@@ -18,12 +18,16 @@
 package org.apache.spark.examples
 
 import java.util.Random
+
 import scala.math.exp
-import org.apache.spark.util.Vector
+
+import breeze.linalg.{Vector, DenseVector}
+
 import org.apache.spark._
 import org.apache.spark.deploy.SparkHadoopUtil
 import org.apache.spark.scheduler.InputFormatInfo
 
+
 /**
  * Logistic regression based classification.
  */
@@ -31,7 +35,7 @@ object SparkHdfsLR {
   val D = 10   // Numer of dimensions
   val rand = new Random(42)
 
-  case class DataPoint(x: Vector, y: Double)
+  case class DataPoint(x: Vector[Double], y: Double)
 
   def parsePoint(line: String): DataPoint = {
     val tok = new java.util.StringTokenizer(line, " ")
@@ -41,7 +45,7 @@ object SparkHdfsLR {
     while (i < D) {
       x(i) = tok.nextToken.toDouble; i += 1
     }
-    DataPoint(new Vector(x), y)
+    DataPoint(new DenseVector(x), y)
   }
 
   def main(args: Array[String]) {
@@ -61,13 +65,13 @@ object SparkHdfsLR {
     val ITERATIONS = args(2).toInt
 
     // Initialize w to a random value
-    var w = Vector(D, _ => 2 * rand.nextDouble - 1)
+    var w = DenseVector.fill(D){2 * rand.nextDouble - 1}
     println("Initial w: " + w)
 
     for (i <- 1 to ITERATIONS) {
       println("On iteration " + i)
       val gradient = points.map { p =>
-        (1 / (1 + exp(-p.y * (w dot p.x))) - 1) * p.y * p.x
+        p.x * (1 / (1 + exp(-p.y * (w.dot(p.x)))) - 1) * p.y
       }.reduce(_ + _)
       w -= gradient
     }
diff --git a/examples/src/main/scala/org/apache/spark/examples/SparkKMeans.scala b/examples/src/main/scala/org/apache/spark/examples/SparkKMeans.scala
index 1a8b21618e..8aa31d7e6a 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SparkKMeans.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SparkKMeans.scala
@@ -18,8 +18,10 @@
 package org.apache.spark.examples
 
 import java.util.Random
+
+import breeze.linalg.{Vector, DenseVector, squaredDistance}
+
 import org.apache.spark.SparkContext
-import org.apache.spark.util.Vector
 import org.apache.spark.SparkContext._
 
 /**
@@ -29,17 +31,17 @@ object SparkKMeans {
   val R = 1000     // Scaling factor
   val rand = new Random(42)
 
-  def parseVector(line: String): Vector = {
-    new Vector(line.split(' ').map(_.toDouble))
+  def parseVector(line: String): Vector[Double] = {
+    DenseVector(line.split(' ').map(_.toDouble))
   }
 
-  def closestPoint(p: Vector, centers: Array[Vector]): Int = {
+  def closestPoint(p: Vector[Double], centers: Array[Vector[Double]]): Int = {
     var index = 0
     var bestIndex = 0
     var closest = Double.PositiveInfinity
 
     for (i <- 0 until centers.length) {
-      val tempDist = p.squaredDist(centers(i))
+      val tempDist = squaredDistance(p, centers(i))
       if (tempDist < closest) {
         closest = tempDist
         bestIndex = i
@@ -69,11 +71,12 @@ object SparkKMeans {
 
       val pointStats = closest.reduceByKey{case ((x1, y1), (x2, y2)) => (x1 + x2, y1 + y2)}
 
-      val newPoints = pointStats.map {pair => (pair._1, pair._2._1 / pair._2._2)}.collectAsMap()
+      val newPoints = pointStats.map {pair =>
+        (pair._1, pair._2._1 * (1.0 / pair._2._2))}.collectAsMap()
 
       tempDist = 0.0
       for (i <- 0 until K) {
-        tempDist += kPoints(i).squaredDist(newPoints(i))
+        tempDist += squaredDistance(kPoints(i), newPoints(i))
       }
 
       for (newP <- newPoints) {
diff --git a/examples/src/main/scala/org/apache/spark/examples/SparkLR.scala b/examples/src/main/scala/org/apache/spark/examples/SparkLR.scala
index 3a2699d4d9..d70ce603bb 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SparkLR.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SparkLR.scala
@@ -18,8 +18,11 @@
 package org.apache.spark.examples
 
 import java.util.Random
+
 import scala.math.exp
-import org.apache.spark.util.Vector
+
+import breeze.linalg.{Vector, DenseVector}
+
 import org.apache.spark._
 
 /**
@@ -32,12 +35,12 @@ object SparkLR {
   val ITERATIONS = 5
   val rand = new Random(42)
 
-  case class DataPoint(x: Vector, y: Double)
+  case class DataPoint(x: Vector[Double], y: Double)
 
   def generateData = {
     def generatePoint(i: Int) = {
       val y = if(i % 2 == 0) -1 else 1
-      val x = Vector(D, _ => rand.nextGaussian + y * R)
+      val x = DenseVector.fill(D){rand.nextGaussian + y * R}
       DataPoint(x, y)
     }
     Array.tabulate(N)(generatePoint)
@@ -54,13 +57,13 @@ object SparkLR {
     val points = sc.parallelize(generateData, numSlices).cache()
 
     // Initialize w to a random value
-    var w = Vector(D, _ => 2 * rand.nextDouble - 1)
+    var w = DenseVector.fill(D){2 * rand.nextDouble - 1}
     println("Initial w: " + w)
 
     for (i <- 1 to ITERATIONS) {
       println("On iteration " + i)
       val gradient = points.map { p =>
-        (1 / (1 + exp(-p.y * (w dot p.x))) - 1) * p.y * p.x
+        p.x * (1 / (1 + exp(-p.y * (w.dot(p.x)))) - 1) * p.y
       }.reduce(_ + _)
       w -= gradient
     }
diff --git a/examples/src/main/scala/org/apache/spark/examples/SparkPageRank.scala b/examples/src/main/scala/org/apache/spark/examples/SparkPageRank.scala
index 45b6e10f3e..60e4a11a21 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SparkPageRank.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SparkPageRank.scala
@@ -20,7 +20,6 @@ package org.apache.spark.examples
 import org.apache.spark.SparkContext._
 import org.apache.spark.SparkContext
 
-
 /**
  * Computes the PageRank of URLs from an input file. Input file should
  * be in format of:
diff --git a/examples/src/main/scala/org/apache/spark/examples/SparkTC.scala b/examples/src/main/scala/org/apache/spark/examples/SparkTC.scala
index eb47cf027c..65bd61abda 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SparkTC.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SparkTC.scala
@@ -17,11 +17,12 @@
 
 package org.apache.spark.examples
 
-import org.apache.spark._
-import SparkContext._
 import scala.util.Random
 import scala.collection.mutable
 
+import org.apache.spark.SparkContext
+import org.apache.spark.SparkContext._
+
 /**
  * Transitive closure on a graph.
  */
diff --git a/examples/src/main/scala/org/apache/spark/examples/SparkTachyonHdfsLR.scala b/examples/src/main/scala/org/apache/spark/examples/SparkTachyonHdfsLR.scala
index 5698d47464..4f558929ad 100644
--- a/examples/src/main/scala/org/apache/spark/examples/SparkTachyonHdfsLR.scala
+++ b/examples/src/main/scala/org/apache/spark/examples/SparkTachyonHdfsLR.scala
@@ -18,13 +18,17 @@
 package org.apache.spark.examples
 
 import java.util.Random
+
 import scala.math.exp
-import org.apache.spark.util.Vector
+
+import breeze.linalg.{Vector, DenseVector}
+
 import org.apache.spark._
 import org.apache.spark.deploy.SparkHadoopUtil
 import org.apache.spark.scheduler.InputFormatInfo
 import org.apache.spark.storage.StorageLevel
 
+
 /**
  * Logistic regression based classification.
  * This example uses Tachyon to persist rdds during computation.
@@ -33,7 +37,7 @@ object SparkTachyonHdfsLR {
   val D = 10   // Numer of dimensions
   val rand = new Random(42)
 
-  case class DataPoint(x: Vector, y: Double)
+  case class DataPoint(x: Vector[Double], y: Double)
 
   def parsePoint(line: String): DataPoint = {
     val tok = new java.util.StringTokenizer(line, " ")
@@ -43,7 +47,7 @@ object SparkTachyonHdfsLR {
     while (i < D) {
       x(i) = tok.nextToken.toDouble; i += 1
     }
-    DataPoint(new Vector(x), y)
+    DataPoint(new DenseVector(x), y)
   }
 
   def main(args: Array[String]) {
@@ -63,13 +67,13 @@ object SparkTachyonHdfsLR {
     val ITERATIONS = args(2).toInt
 
     // Initialize w to a random value
-    var w = Vector(D, _ => 2 * rand.nextDouble - 1)
+    var w = DenseVector.fill(D){2 * rand.nextDouble - 1}
     println("Initial w: " + w)
 
     for (i <- 1 to ITERATIONS) {
       println("On iteration " + i)
       val gradient = points.map { p =>
-        (1 / (1 + exp(-p.y * (w dot p.x))) - 1) * p.y * p.x
+        p.x * (1 / (1 + exp(-p.y * (w.dot(p.x)))) - 1) * p.y
       }.reduce(_ + _)
       w -= gradient
     }