spark JavaUnivariateFeatureSelectorExample 源码

spark JavaUnivariateFeatureSelectorExample 代码

文件路径：/examples/src/main/java/org/apache/spark/examples/ml/JavaUnivariateFeatureSelectorExample.java

/*
 * 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.ml;

import org.apache.spark.sql.Dataset;
import org.apache.spark.sql.SparkSession;

// $example on$
import java.util.Arrays;
import java.util.List;

import org.apache.spark.ml.feature.UnivariateFeatureSelector;
import org.apache.spark.ml.linalg.VectorUDT;
import org.apache.spark.ml.linalg.Vectors;
import org.apache.spark.sql.Row;
import org.apache.spark.sql.RowFactory;
import org.apache.spark.sql.types.*;
// $example off$

/**
 * An example for UnivariateFeatureSelector.
 * Run with
 * <pre>
 * bin/run-example ml.JavaUnivariateFeatureSelectorExample
 * </pre>
 */
public class JavaUnivariateFeatureSelectorExample {
  public static void main(String[] args) {
    SparkSession spark = SparkSession
      .builder()
      .appName("JavaUnivariateFeatureSelectorExample")
      .getOrCreate();

    // $example on$
    List<Row> data = Arrays.asList(
      RowFactory.create(1, Vectors.dense(1.7, 4.4, 7.6, 5.8, 9.6, 2.3), 3.0),
      RowFactory.create(2, Vectors.dense(8.8, 7.3, 5.7, 7.3, 2.2, 4.1), 2.0),
      RowFactory.create(3, Vectors.dense(1.2, 9.5, 2.5, 3.1, 8.7, 2.5), 3.0),
      RowFactory.create(4, Vectors.dense(3.7, 9.2, 6.1, 4.1, 7.5, 3.8), 2.0),
      RowFactory.create(5, Vectors.dense(8.9, 5.2, 7.8, 8.3, 5.2, 3.0), 4.0),
      RowFactory.create(6, Vectors.dense(7.9, 8.5, 9.2, 4.0, 9.4, 2.1), 4.0)
    );
    StructType schema = new StructType(new StructField[]{
      new StructField("id", DataTypes.IntegerType, false, Metadata.empty()),
      new StructField("features", new VectorUDT(), false, Metadata.empty()),
      new StructField("label", DataTypes.DoubleType, false, Metadata.empty())
    });

    Dataset<Row> df = spark.createDataFrame(data, schema);

    UnivariateFeatureSelector selector = new UnivariateFeatureSelector()
      .setFeatureType("continuous")
      .setLabelType("categorical")
      .setSelectionMode("numTopFeatures")
      .setSelectionThreshold(1)
      .setFeaturesCol("features")
      .setLabelCol("label")
      .setOutputCol("selectedFeatures");

    Dataset<Row> result = selector.fit(df).transform(df);

    System.out.println("UnivariateFeatureSelector output with top "
        + selector.getSelectionThreshold() + " features selected using f_classif");
    result.show();

    // $example off$
    spark.stop();
  }
}

相关信息

spark 源码目录

相关文章

spark JavaAFTSurvivalRegressionExample 源码

spark JavaALSExample 源码

spark JavaBinarizerExample 源码

spark JavaBisectingKMeansExample 源码

spark JavaBucketedRandomProjectionLSHExample 源码

spark JavaBucketizerExample 源码

spark JavaChiSqSelectorExample 源码

spark JavaChiSquareTestExample 源码

spark JavaCorrelationExample 源码

spark JavaCountVectorizerExample 源码