Repository: spark Updated Branches: refs/heads/master c0ccd2564 -> e1a1ff810
[SPARK-5503][MLLIB] Example code for Power Iteration Clustering Author: sboeschhuawei <stephen.boe...@huawei.com> Closes #4495 from javadba/picexamples and squashes the following commits: 3c84b14 [sboeschhuawei] PIC Examples updates from Xiangrui's comments round 5 2878675 [sboeschhuawei] Fourth round with xiangrui on PICExample d7ac350 [sboeschhuawei] Updates to PICExample from Xiangrui's comments round 3 d7f0cba [sboeschhuawei] Updates to PICExample from Xiangrui's comments round 3 cef28f4 [sboeschhuawei] Further updates to PICExample from Xiangrui's comments f7ff43d [sboeschhuawei] Update to PICExample from Xiangrui's comments efeec45 [sboeschhuawei] Update to PICExample from Xiangrui's comments 03e8de4 [sboeschhuawei] Added PICExample c509130 [sboeschhuawei] placeholder for pic examples 5864d4a [sboeschhuawei] placeholder for pic examples Project: http://git-wip-us.apache.org/repos/asf/spark/repo Commit: http://git-wip-us.apache.org/repos/asf/spark/commit/e1a1ff81 Tree: http://git-wip-us.apache.org/repos/asf/spark/tree/e1a1ff81 Diff: http://git-wip-us.apache.org/repos/asf/spark/diff/e1a1ff81 Branch: refs/heads/master Commit: e1a1ff8108463ca79299ec0eb555a0c8db9dffa0 Parents: c0ccd25 Author: sboeschhuawei <stephen.boe...@huawei.com> Authored: Fri Feb 13 09:45:57 2015 -0800 Committer: Xiangrui Meng <m...@databricks.com> Committed: Fri Feb 13 09:45:57 2015 -0800 ---------------------------------------------------------------------- .../mllib/PowerIterationClusteringExample.scala | 160 +++++++++++++++++++ 1 file changed, 160 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/spark/blob/e1a1ff81/examples/src/main/scala/org/apache/spark/examples/mllib/PowerIterationClusteringExample.scala ---------------------------------------------------------------------- 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 new file mode 100644 index 0000000..b2373ad --- /dev/null +++ b/examples/src/main/scala/org/apache/spark/examples/mllib/PowerIterationClusteringExample.scala @@ -0,0 +1,160 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.spark.examples.mllib + +import org.apache.log4j.{Level, Logger} +import scopt.OptionParser + +import org.apache.spark.mllib.clustering.PowerIterationClustering +import org.apache.spark.rdd.RDD +import org.apache.spark.{SparkConf, SparkContext} + +/** + * An example Power Iteration Clustering http://www.icml2010.org/papers/387.pdf app. + * Takes an input of K concentric circles and the number of points in the innermost circle. + * The output should be K clusters - each cluster containing precisely the points associated + * with each of the input circles. + * + * Run with + * {{{ + * ./bin/run-example mllib.PowerIterationClusteringExample [options] + * + * Where options include: + * k: Number of circles/clusters + * 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] + * + * + * 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 + ) extends AbstractParams[Params] + + def main(args: Array[String]) { + val defaultParams = Params() + + val parser = new OptionParser[Params]("PIC Circles") { + head("PowerIterationClusteringExample: an example PIC app using concentric circles.") + opt[Int]('k', "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}") + .action((x, c) => c.copy(numPoints = x)) + opt[Int]("maxIterations") + .text(s"number of iterations, default: ${defaultParams.maxIterations}") + .action((x, c) => c.copy(maxIterations = x)) + opt[Int]('r', "r") + .text(s"radius of outermost circle, default: ${defaultParams.outerRadius}") + .action((x, c) => c.copy(numPoints = x)) + } + + parser.parse(args, defaultParams).map { params => + run(params) + }.getOrElse { + sys.exit(1) + } + } + + def run(params: Params) { + val conf = new SparkConf() + .setMaster("local") + .setAppName(s"PowerIterationClustering with $params") + val sc = new SparkContext(conf) + + Logger.getRootLogger.setLevel(Level.WARN) + + val circlesRdd = generateCirclesRdd(sc, params.k, params.numPoints, params.outerRadius) + val model = new PowerIterationClustering() + .setK(params.k) + .setMaxIterations(params.maxIterations) + .run(circlesRdd) + + val clusters = model.assignments.collect.groupBy(_._2).mapValues(_.map(_._1)) + val assignments = clusters.toList.sortBy { case (k, v) => v.length} + val assignmentsStr = assignments + .map { case (k, v) => + s"$k -> ${v.sorted.mkString("[", ",", "]")}" + }.mkString(",") + val sizesStr = assignments.map { + _._2.size + }.sorted.mkString("(", ",", ")") + println(s"Cluster assignments: $assignmentsStr\ncluster sizes: $sizesStr") + + sc.stop() + } + + def generateCircle(radius: Double, n: Int) = { + Seq.tabulate(n) { i => + val theta = 2.0 * math.Pi * i / n + (radius * math.cos(theta), radius * math.sin(theta)) + } + } + + 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)) + }.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))) + } else { + None + } + } + distancesRdd + } + + /** + * Gaussian Similarity: http://en.wikipedia.org/wiki/Radial_basis_function_kernel + */ + def gaussianSimilarity(p1: (Double, Double), p2: (Double, Double), sigma: Double) = { + val coeff = 1.0 / (math.sqrt(2.0 * math.Pi) * sigma) + val expCoeff = -1.0 / 2.0 * math.pow(sigma, 2.0) + 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((p1._1 - p2._1) * (p1._1 - p2._1) + (p1._2 - p2._2) * (p1._2 - p2._2)) + } + + +} --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@spark.apache.org For additional commands, e-mail: commits-h...@spark.apache.org
