From f150b6e76c56ed6f604e6dbda7bce6b6278929fb Mon Sep 17 00:00:00 2001
From: "Lian, Cheng" <rhythm.mail@gmail.com>
Date: Sun, 29 Dec 2013 17:13:01 +0800
Subject: Response to Reynold's comments

---
 .../spark/mllib/classification/NaiveBayes.scala    | 26 +++++++++++++---------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/mllib/src/main/scala/org/apache/spark/mllib/classification/NaiveBayes.scala b/mllib/src/main/scala/org/apache/spark/mllib/classification/NaiveBayes.scala
index 2bc4c5afc0..d0f3a368e8 100644
--- a/mllib/src/main/scala/org/apache/spark/mllib/classification/NaiveBayes.scala
+++ b/mllib/src/main/scala/org/apache/spark/mllib/classification/NaiveBayes.scala
@@ -17,20 +17,22 @@
 
 package org.apache.spark.mllib.classification
 
+import org.jblas.DoubleMatrix
+
 import org.apache.spark.Logging
 import org.apache.spark.mllib.regression.LabeledPoint
 import org.apache.spark.rdd.RDD
 import org.apache.spark.SparkContext._
-import org.jblas.DoubleMatrix
 
 /**
  * Model for Naive Bayes Classifiers.
  *
- * @param weightPerLabel Weights computed for every label, which's dimension is C.
- * @param weightMatrix Weights computed for every label and feature, which's dimension is CXD
+ * @param weightPerLabel Weights computed for every label, whose dimension is C.
+ * @param weightMatrix Weights computed for every label and feature, whose dimension is CXD
  */
-class NaiveBayesModel(val weightPerLabel: Array[Double],
-    val weightMatrix: Array[Array[Double]])
+class NaiveBayesModel(
+    @transient val weightPerLabel: Array[Double],
+    @transient val weightMatrix: Array[Array[Double]])
   extends ClassificationModel with Serializable {
 
   // Create a column vector that can be used for predictions
@@ -50,7 +52,12 @@ class NaiveBayes private (val lambda: Double = 1.0) // smoothing parameter
   extends Serializable with Logging {
 
   private def vectorAdd(v1: Array[Double], v2: Array[Double]) = {
-    v1.zip(v2).map(pair => pair._1 + pair._2)
+    var i = 0
+    while (i < v1.length) {
+      v1(i) += v2(i)
+      i += 1
+    }
+    v1
   }
 
   /**
@@ -79,8 +86,8 @@ class NaiveBayes private (val lambda: Double = 1.0) // smoothing parameter
     // considerably expensive.
     val N = collected.values.map(_._1).sum
     val logDenom = math.log(N + C * lambda)
-    val weightPerLabel = Array.fill[Double](C)(0)
-    val weightMatrix = Array.fill[Array[Double]](C)(null)
+    val weightPerLabel = new Array[Double](C)
+    val weightMatrix = new Array[Array[Double]](C)
 
     for ((label, (_, labelWeight, weights)) <- collected) {
       weightPerLabel(label) = labelWeight - logDenom
@@ -100,8 +107,7 @@ object NaiveBayes {
    * @param input RDD of (label, array of features) pairs.
    * @param lambda smooth parameter
    */
-  def train(C: Int, D: Int, input: RDD[LabeledPoint],
-      lambda: Double = 1.0): NaiveBayesModel = {
+  def train(C: Int, D: Int, input: RDD[LabeledPoint], lambda: Double = 1.0): NaiveBayesModel = {
     new NaiveBayes(lambda).run(C, D, input)
   }
 }
-- 
cgit v1.2.3