diff options
Diffstat (limited to 'examples/src')
-rw-r--r-- | examples/src/main/scala/org/apache/spark/examples/mllib/PowerIterationClusteringExample.scala | 53 |
1 files changed, 21 insertions, 32 deletions
diff --git a/examples/src/main/scala/org/apache/spark/examples/mllib/PowerIterationClusteringExample.scala b/examples/src/main/scala/org/apache/spark/examples/mllib/PowerIterationClusteringExample.scala index 9208d8e245..bb9c1cbca9 100644 --- a/examples/src/main/scala/org/apache/spark/examples/mllib/PowerIterationClusteringExample.scala +++ b/examples/src/main/scala/org/apache/spark/examples/mllib/PowerIterationClusteringExample.scala @@ -40,27 +40,23 @@ import org.apache.spark.rdd.RDD * n: Number of sampled points on innermost circle.. There are proportionally more points * within the outer/larger circles * maxIterations: Number of Power Iterations - * outerRadius: radius of the outermost of the concentric circles * }}} * * Here is a sample run and output: * - * ./bin/run-example mllib.PowerIterationClusteringExample -k 3 --n 30 --maxIterations 15 - * - * Cluster assignments: 1 -> [0,1,2,3,4],2 -> [5,6,7,8,9,10,11,12,13,14], - * 0 -> [15,16,17,18,19,20,21,22,23,24,25,26,27,28,29] + * ./bin/run-example mllib.PowerIterationClusteringExample -k 2 --n 10 --maxIterations 15 * + * Cluster assignments: 1 -> [0,1,2,3,4,5,6,7,8,9], + * 0 -> [10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29] * * If you use it as a template to create your own app, please use `spark-submit` to submit your app. */ object PowerIterationClusteringExample { case class Params( - input: String = null, - k: Int = 3, - numPoints: Int = 5, - maxIterations: Int = 10, - outerRadius: Double = 3.0 + k: Int = 2, + numPoints: Int = 10, + maxIterations: Int = 15 ) extends AbstractParams[Params] def main(args: Array[String]) { @@ -69,7 +65,7 @@ object PowerIterationClusteringExample { val parser = new OptionParser[Params]("PowerIterationClusteringExample") { head("PowerIterationClusteringExample: an example PIC app using concentric circles.") opt[Int]('k', "k") - .text(s"number of circles (/clusters), default: ${defaultParams.k}") + .text(s"number of circles (clusters), default: ${defaultParams.k}") .action((x, c) => c.copy(k = x)) opt[Int]('n', "n") .text(s"number of points in smallest circle, default: ${defaultParams.numPoints}") @@ -77,9 +73,6 @@ object PowerIterationClusteringExample { opt[Int]("maxIterations") .text(s"number of iterations, default: ${defaultParams.maxIterations}") .action((x, c) => c.copy(maxIterations = x)) - opt[Double]('r', "r") - .text(s"radius of outermost circle, default: ${defaultParams.outerRadius}") - .action((x, c) => c.copy(outerRadius = x)) } parser.parse(args, defaultParams).map { params => @@ -97,20 +90,21 @@ object PowerIterationClusteringExample { Logger.getRootLogger.setLevel(Level.WARN) - val circlesRdd = generateCirclesRdd(sc, params.k, params.numPoints, params.outerRadius) + val circlesRdd = generateCirclesRdd(sc, params.k, params.numPoints) val model = new PowerIterationClustering() .setK(params.k) .setMaxIterations(params.maxIterations) + .setInitializationMode("degree") .run(circlesRdd) val clusters = model.assignments.collect().groupBy(_.cluster).mapValues(_.map(_.id)) - val assignments = clusters.toList.sortBy { case (k, v) => v.length} + val assignments = clusters.toList.sortBy { case (k, v) => v.length } val assignmentsStr = assignments .map { case (k, v) => s"$k -> ${v.sorted.mkString("[", ",", "]")}" - }.mkString(",") + }.mkString(", ") val sizesStr = assignments.map { - _._2.size + _._2.length }.sorted.mkString("(", ",", ")") println(s"Cluster assignments: $assignmentsStr\ncluster sizes: $sizesStr") @@ -124,20 +118,17 @@ object PowerIterationClusteringExample { } } - def generateCirclesRdd(sc: SparkContext, - nCircles: Int = 3, - nPoints: Int = 30, - outerRadius: Double): RDD[(Long, Long, Double)] = { - - val radii = Array.tabulate(nCircles) { cx => outerRadius / (nCircles - cx)} - val groupSizes = Array.tabulate(nCircles) { cx => (cx + 1) * nPoints} - val points = (0 until nCircles).flatMap { cx => - generateCircle(radii(cx), groupSizes(cx)) + def generateCirclesRdd( + sc: SparkContext, + nCircles: Int, + nPoints: Int): RDD[(Long, Long, Double)] = { + val points = (1 to nCircles).flatMap { i => + generateCircle(i, i * nPoints) }.zipWithIndex val rdd = sc.parallelize(points) val distancesRdd = rdd.cartesian(rdd).flatMap { case (((x0, y0), i0), ((x1, y1), i1)) => if (i0 < i1) { - Some((i0.toLong, i1.toLong, gaussianSimilarity((x0, y0), (x1, y1), 1.0))) + Some((i0.toLong, i1.toLong, gaussianSimilarity((x0, y0), (x1, y1)))) } else { None } @@ -148,11 +139,9 @@ object PowerIterationClusteringExample { /** * Gaussian Similarity: http://en.wikipedia.org/wiki/Radial_basis_function_kernel */ - def gaussianSimilarity(p1: (Double, Double), p2: (Double, Double), sigma: Double): Double = { - val coeff = 1.0 / (math.sqrt(2.0 * math.Pi) * sigma) - val expCoeff = -1.0 / 2.0 * math.pow(sigma, 2.0) + def gaussianSimilarity(p1: (Double, Double), p2: (Double, Double)): Double = { val ssquares = (p1._1 - p2._1) * (p1._1 - p2._1) + (p1._2 - p2._2) * (p1._2 - p2._2) - coeff * math.exp(expCoeff * ssquares) + math.exp(-ssquares / 2.0) } } // scalastyle:on println |