Scala LogisticRegression类代码示例

//设置package包名称以及导入依赖的类
package com.ferhtaydn.rater

import org.apache.spark.SparkContext
import org.apache.spark.ml.Pipeline
import org.apache.spark.ml.classification.LogisticRegression
import org.apache.spark.ml.evaluation.BinaryClassificationEvaluator
import org.apache.spark.ml.feature.{ StringIndexerModel, VectorAssembler }
import org.apache.spark.ml.tuning.{ CrossValidator, CrossValidatorModel, ParamGridBuilder }
import org.apache.spark.mllib.linalg.Matrix
import org.apache.spark.sql.{ DataFrame, Row, SQLContext }

class LRCV(sc: SparkContext) {

  implicit val sqlContext = new SQLContext(sc)

  val lr = new LogisticRegression().setMaxIter(10).setFeaturesCol("scaledFeatures")

  val paramGrid = new ParamGridBuilder()
    .addGrid(lr.regParam, Array(0.1, 0.01))
    .build()

  val assembler = new VectorAssembler()
    .setInputCols(Array("gender", "age", "weight", "height", "indexedJob"))
    .setOutputCol("features")

  val pipeline = new Pipeline()
    .setStages(Array(assembler, standardScaler("features"), lr))

  val cv = new CrossValidator()
    .setEstimator(pipeline)
    .setEvaluator(new BinaryClassificationEvaluator)
    .setEstimatorParamMaps(paramGrid)
    .setNumFolds(10)

  def train(df: DataFrame): (StringIndexerModel, CrossValidatorModel, Matrix) = {

    // need to index strings on all data to not missing the job fields.
    // other alternative can be manually assign values for each job like gender.
    val indexerModel = stringIndexer("job").fit(df)
    val indexed = indexerModel.transform(df)

    val splits = indexed.randomSplit(Array(0.8, 0.2))
    val training = splits(0).cache()
    val test = splits(1)

    val cvModel = cv.fit(training)

    val predictionAndLabels = cvModel
      .transform(test)
      .select("label", "prediction").map {
        case Row(label: Double, prediction: Double) ?
          (prediction, label)
      }

    printBinaryMetrics(predictionAndLabels)

    (indexerModel, cvModel, confusionMatrix(predictionAndLabels))

  }

} 

//设置package包名称以及导入依赖的类
import io.hydrosphere.mist.api._
import io.hydrosphere.mist.api.ml._
import org.apache.spark.ml.Pipeline
import org.apache.spark.ml.classification.LogisticRegression
import org.apache.spark.ml.feature.{HashingTF, Tokenizer}
import org.apache.spark.sql.SparkSession


object MLClassification extends MLMistJob {
  def session: SparkSession = SparkSession
    .builder()
    .appName(context.appName)
    .config(context.getConf)
    .getOrCreate()

  def train(): Map[String, Any] = {
    val training = session.createDataFrame(Seq(
      (0L, "a b c d e spark", 1.0),
      (1L, "b d", 0.0),
      (2L, "spark f g h", 1.0),
      (3L, "hadoop mapreduce", 0.0)
    )).toDF("id", "text", "label")

    val tokenizer = new Tokenizer()
      .setInputCol("text")
      .setOutputCol("words")
    val hashingTF = new HashingTF()
      .setNumFeatures(1000)
      .setInputCol(tokenizer.getOutputCol)
      .setOutputCol("features")
    val lr = new LogisticRegression()
      .setMaxIter(10)
      .setRegParam(0.01)
    val pipeline = new Pipeline()
      .setStages(Array(tokenizer, hashingTF, lr))

    val model = pipeline.fit(training)

    model.write.overwrite().save("regression")

    Map.empty[String, Any]
  }

  def serve(text: List[String]): Map[String, Any] = {
    import LocalPipelineModel._

    val pipeline = PipelineLoader.load(s"regression")
    val data = LocalData(
      LocalDataColumn("text", text)
    )
    val result: LocalData = pipeline.transform(data)
    Map("result" -> result.select("text", "prediction").toMapList)
  }
} 

//设置package包名称以及导入依赖的类
package com.zobot.ai.spark

import breeze.linalg.Matrix
import com.zobot.ai.spark.helpers.LogisticRegressionHelpers
import org.apache.spark.ml.classification.LogisticRegression
import org.apache.spark.ml.linalg.Vectors
import org.specs2.Specification

class TestLogisticRegression extends Specification {
  def is = s2"""
                Logistic Regression
                  can train model $testTrainLogisticRegressionModel
      """

  val context = new Context().spark

  def testTrainLogisticRegressionModel = {
    val model = LogisticRegressionHelpers.trainModel(new LogisticRegression, context.createDataFrame(Seq(
      (1.0, Vectors.dense(0.0, 1.1, 0.1)),
      (0.0, Vectors.dense(2.0, 1.0, -1.0)),
      (0.0, Vectors.dense(2.0, 1.3, 1.0)),
      (1.0, Vectors.dense(0.0, 1.2, -0.5))
    )).toDF("label", "features"))

    model.coefficientMatrix.toString().must_==("-19.086478256375067  16.278339464295065  -2.494930802874724  ")
  }
} 

//设置package包名称以及导入依赖的类
package org.apache.spark.examples.ml

import org.apache.spark.ml.classification.LogisticRegression
import org.apache.spark.sql.SQLContext
import org.apache.spark.SparkConf
import org.apache.spark.SparkContext

object LogisticRegressionWithElasticNetExample {

  def main(args: Array[String]): Unit = {
    val conf = new SparkConf().setMaster("local").setAppName("LogisticRegressionWithElasticNetExample")
    val sc = new SparkContext(conf)
    val sqlCtx = new SQLContext(sc)

    // $example on$
    // Load training data
    val training = sqlCtx.read.format("libsvm").load("data/mllib/sample_libsvm_data.txt")

    val lr = new LogisticRegression()
      .setMaxIter(10)
      .setRegParam(0.3)
      .setElasticNetParam(0.8)

    // Fit the model
    val lrModel = lr.fit(training)

    // Print the coefficients and intercept for logistic regression
    println(s"Coefficients: ${lrModel.coefficients} Intercept: ${lrModel.intercept}")
    // $example off$

    sc.stop()
  }
} 

//设置package包名称以及导入依赖的类
package applications.mining

import config.paramconf.ClassParams
import functions.Preprocessor
import org.apache.log4j.{Level, Logger}
import org.apache.spark.ml.classification.LogisticRegression
import org.apache.spark.ml.feature._
import org.apache.spark.sql.SparkSession


object TrainNewsClassWithLRDemo extends Serializable {
  def main(args: Array[String]): Unit = {
    Logger.getLogger("org").setLevel(Level.WARN)

    val spark = SparkSession
      .builder
      .master("local[2]")
      .appName("train news with LR Demo")
      .getOrCreate()

    val args = Array("ckooc-ml/data/classnews/train")
    val filePath = args(0)

    import spark.implicits._
    val data = spark.sparkContext.textFile(filePath).flatMap { line =>
      val tokens: Array[String] = line.split("\u00ef")
      if (tokens.length > 3) Some((tokens(0), tokens(1), tokens(2), tokens(3))) else None
    }.toDF("label", "title", "time", "content")
    data.persist()

    val preprocessor = new Preprocessor
    val pipeline = preprocessor.preprocess(data)

    //LR????
    val params = new ClassParams
    val logisticRegression = new LogisticRegression()
      .setTol(params.converTol)
      .setMaxIter(params.maxIteration)
      .setRegParam(params.regParam)
      .setElasticNetParam(params.elasticNetParam)
      .setLabelCol("indexedLabel")
      .setFeaturesCol("features")

    val indexModel = pipeline.getStages(1).asInstanceOf[StringIndexerModel]
    //?????
    val labelConverter = new IndexToString()
      .setLabels(indexModel.labels)
      .setInputCol(logisticRegression.getPredictionCol)
      .setOutputCol("predictedLabel")

    val stages = pipeline.getStages ++ Array(logisticRegression, labelConverter)
    pipeline.setStages(stages)

    val model = pipeline.fit(data)
    model.write.overwrite().save(params.LRModelPath)

    data.unpersist()
    spark.stop()
  }
} 

//设置package包名称以及导入依赖的类
package com.zobot.ai.spark.helpers

import org.apache.spark.ml.classification.{LogisticRegression, LogisticRegressionModel}
import org.apache.spark.ml.linalg.Vector
import org.apache.spark.sql.{DataFrame, Row}

object LogisticRegressionHelpers {
  case class ModelTestResults (
    features: Vector,
    label: Double,
    probability: Vector,
    prediction: Double
  )

  def trainModel(estimator: LogisticRegression, trainingSet: DataFrame): LogisticRegressionModel = estimator.fit(trainingSet)

  def testModel(transformer: LogisticRegressionModel, testSet: DataFrame): LogisticRegressionModel = {
    transformer.transform(testSet).select("features", "label", "myProbability", "prediction").collect().foreach {
      case Row(features: Vector, label: Double, prob: Vector, prediction: Double) =>
        ModelTestResults(features, label, prob, prediction)
    }
    transformer
  }
} 

//设置package包名称以及导入依赖的类
package ml

import model.{ AppError, AppReader }
import org.apache.spark.ml.Pipeline
import org.apache.spark.ml.classification.LogisticRegression
import org.apache.spark.ml.feature._

import scalaz.{ \/, Kleisli }

trait PipelineBuilder {
  def buildLogRegr(inputColName: String, labelColName: String): AppReader[Pipeline] = AppReader[Pipeline] {
    spark ?
      \/.fromTryCatchNonFatal {
        val tokenizer = new Tokenizer()
          .setInputCol(inputColName)
          .setOutputCol("words")

        val stopWordsRemover = new StopWordsRemover()
          .setInputCol("words")
          .setOutputCol("words_filtered")

        

        val hashingTF = new HashingTF()
          .setInputCol("words")
          .setOutputCol("rawFeatures")
          .setNumFeatures(700)

        val idf = new IDF()
          .setInputCol("rawFeatures")
          .setOutputCol("features")

        val lr = new LogisticRegression()
          .setMaxIter(1000)
          .setRegParam(0.05)
          .setFeaturesCol("features")
          .setLabelCol(labelColName)

        val pipeline = new Pipeline()
          .setStages(Array(tokenizer, stopWordsRemover, hashingTF, idf, lr))

        pipeline
      }
  }
}