[SPARK-7678] [ml] Fix default random seed in HasSeed

mllib/src/main/scala/org/apache/spark/ml/feature/Word2Vec.scala

@@ -68,7 +68,6 @@ private[feature] trait Word2VecBase extends Params
 
   setDefault(stepSize -> 0.025)
   setDefault(maxIter -> 1)
-  setDefault(seed -> 42L)
 
   /**
    * Validate and transform the input schema.

mllib/src/main/scala/org/apache/spark/ml/param/shared/SharedParamsCodeGen.scala

@@ -53,7 +53,7 @@ private[shared] object SharedParamsCodeGen {
       ParamDesc[Int]("checkpointInterval", "checkpoint interval (>= 1)",
         isValid = "ParamValidators.gtEq(1)"),
       ParamDesc[Boolean]("fitIntercept", "whether to fit an intercept term", Some("true")),
-      ParamDesc[Long]("seed", "random seed", Some("Utils.random.nextLong()")),
+      ParamDesc[Long]("seed", "random seed", Some("this.getClass.getName.hashCode.toLong")),
       ParamDesc[Double]("elasticNetParam", "the ElasticNet mixing parameter, in range [0, 1]." +
         " For alpha = 0, the penalty is an L2 penalty. For alpha = 1, it is an L1 penalty.",
         isValid = "ParamValidators.inRange(0, 1)"),

mllib/src/main/scala/org/apache/spark/ml/param/shared/sharedParams.scala

@@ -232,7 +232,7 @@ private[ml] trait HasFitIntercept extends Params {
 }
 
 /**
- * (private[ml]) Trait for shared param seed (default: Utils.random.nextLong()).
+ * (private[ml]) Trait for shared param seed (default: this.getClass.getName.hashCode.toLong).
  */
 private[ml] trait HasSeed extends Params {
 
@@ -242,7 +242,7 @@ private[ml] trait HasSeed extends Params {
    */
   final val seed: LongParam = new LongParam(this, "seed", "random seed")
 
-  setDefault(seed, Utils.random.nextLong())
+  setDefault(seed, this.getClass.getName.hashCode.toLong)
 
   /** @group getParam */
   final def getSeed: Long = $(seed)

mllib/src/main/scala/org/apache/spark/ml/recommendation/ALS.scala

@@ -148,7 +148,7 @@ private[recommendation] trait ALSParams extends Params with HasMaxIter with HasR
 
   setDefault(rank -> 10, maxIter -> 10, regParam -> 0.1, numUserBlocks -> 10, numItemBlocks -> 10,
     implicitPrefs -> false, alpha -> 1.0, userCol -> "user", itemCol -> "item",
-    ratingCol -> "rating", nonnegative -> false, checkpointInterval -> 10, seed -> 0L)
+    ratingCol -> "rating", nonnegative -> false, checkpointInterval -> 10)
 
   /**
    * Validates and transforms the input schema.

mllib/src/test/scala/org/apache/spark/ml/feature/Word2VecSuite.scala

@@ -52,6 +52,7 @@ class Word2VecSuite extends FunSuite with MLlibTestSparkContext {
       .setVectorSize(3)
       .setInputCol("text")
       .setOutputCol("result")
+      .setSeed(42L)
       .fit(docDF)
 
     model.transform(docDF).select("result", "expected").collect().foreach {

mllib/src/test/scala/org/apache/spark/ml/recommendation/ALSSuite.scala

@@ -345,6 +345,7 @@ class ALSSuite extends FunSuite with MLlibTestSparkContext with Logging {
       .setImplicitPrefs(implicitPrefs)
       .setNumUserBlocks(numUserBlocks)
       .setNumItemBlocks(numItemBlocks)
+      .setSeed(0)
     val alpha = als.getAlpha
     val model = als.fit(training.toDF())
     val predictions = model.transform(test.toDF())
@@ -425,17 +426,18 @@ class ALSSuite extends FunSuite with MLlibTestSparkContext with Logging {
     val (ratings, _) = genImplicitTestData(numUsers = 20, numItems = 40, rank = 2, noiseStd = 0.01)
 
     val longRatings = ratings.map(r => Rating(r.user.toLong, r.item.toLong, r.rating))
-    val (longUserFactors, _) = ALS.train(longRatings, rank = 2, maxIter = 4)
+    val (longUserFactors, _) = ALS.train(longRatings, rank = 2, maxIter = 4, seed = 0)
     assert(longUserFactors.first()._1.getClass === classOf[Long])
 
     val strRatings = ratings.map(r => Rating(r.user.toString, r.item.toString, r.rating))
-    val (strUserFactors, _) = ALS.train(strRatings, rank = 2, maxIter = 4)
+    val (strUserFactors, _) = ALS.train(strRatings, rank = 2, maxIter = 4, seed = 0)
     assert(strUserFactors.first()._1.getClass === classOf[String])
   }
 
   test("nonnegative constraint") {
     val (ratings, _) = genImplicitTestData(numUsers = 20, numItems = 40, rank = 2, noiseStd = 0.01)
-    val (userFactors, itemFactors) = ALS.train(ratings, rank = 2, maxIter = 4, nonnegative = true)
+    val (userFactors, itemFactors) =
+      ALS.train(ratings, rank = 2, maxIter = 4, nonnegative = true, seed = 0)
     def isNonnegative(factors: RDD[(Int, Array[Float])]): Boolean = {
       factors.values.map { _.forall(_ >= 0.0) }.reduce(_ && _)
     }
@@ -459,7 +461,7 @@ class ALSSuite extends FunSuite with MLlibTestSparkContext with Logging {
   test("partitioner in returned factors") {
     val (ratings, _) = genImplicitTestData(numUsers = 20, numItems = 40, rank = 2, noiseStd = 0.01)
     val (userFactors, itemFactors) = ALS.train(
-      ratings, rank = 2, maxIter = 4, numUserBlocks = 3, numItemBlocks = 4)
+      ratings, rank = 2, maxIter = 4, numUserBlocks = 3, numItemBlocks = 4, seed = 0)
     for ((tpe, factors) <- Seq(("User", userFactors), ("Item", itemFactors))) {
       assert(userFactors.partitioner.isDefined, s"$tpe factors should have partitioner.")
       val part = userFactors.partitioner.get
@@ -476,8 +478,8 @@ class ALSSuite extends FunSuite with MLlibTestSparkContext with Logging {
 
   test("als with large number of iterations") {
     val (ratings, _) = genExplicitTestData(numUsers = 4, numItems = 4, rank = 1)
-    ALS.train(ratings, rank = 1, maxIter = 50, numUserBlocks = 2, numItemBlocks = 2)
-    ALS.train(
-      ratings, rank = 1, maxIter = 50, numUserBlocks = 2, numItemBlocks = 2, implicitPrefs = true)
+    ALS.train(ratings, rank = 1, maxIter = 50, numUserBlocks = 2, numItemBlocks = 2, seed = 0)
+    ALS.train(ratings, rank = 1, maxIter = 50, numUserBlocks = 2, numItemBlocks = 2,
+      implicitPrefs = true, seed = 0)
   }
 }