examples/mllib/JavaKernelDensityEstimationExample.java

0001 /*
0002  * Licensed to the Apache Software Foundation (ASF) under one or more
0003  * contributor license agreements.  See the NOTICE file distributed with
0004  * this work for additional information regarding copyright ownership.
0005  * The ASF licenses this file to You under the Apache License, Version 2.0
0006  * (the "License"); you may not use this file except in compliance with
0007  * the License.  You may obtain a copy of the License at
0008  *
0009  *    http://www.apache.org/licenses/LICENSE-2.0
0010  *
0011  * Unless required by applicable law or agreed to in writing, software
0012  * distributed under the License is distributed on an "AS IS" BASIS,
0013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
0014  * See the License for the specific language governing permissions and
0015  * limitations under the License.
0016  */
0017
0018 package org.apache.spark.examples.mllib;
0019
0020 import org.apache.spark.SparkConf;
0021 import org.apache.spark.api.java.JavaSparkContext;
0022 // $example on$
0023 import java.util.Arrays;
0024
0025 import org.apache.spark.api.java.JavaRDD;
0026 import org.apache.spark.mllib.stat.KernelDensity;
0027 // $example off$
0028
0029 public class JavaKernelDensityEstimationExample {
0030   public static void main(String[] args) {
0031
0032     SparkConf conf = new SparkConf().setAppName("JavaKernelDensityEstimationExample");
0033     JavaSparkContext jsc = new JavaSparkContext(conf);
0034
0035     // $example on$
0036     // an RDD of sample data
0037     JavaRDD<Double> data = jsc.parallelize(
0038       Arrays.asList(1.0, 1.0, 1.0, 2.0, 3.0, 4.0, 5.0, 5.0, 6.0, 7.0, 8.0, 9.0, 9.0));
0039
0040     // Construct the density estimator with the sample data
0041     // and a standard deviation for the Gaussian kernels
0042     KernelDensity kd = new KernelDensity().setSample(data).setBandwidth(3.0);
0043
0044     // Find density estimates for the given values
0045     double[] densities = kd.estimate(new double[]{-1.0, 2.0, 5.0});
0046
0047     System.out.println(Arrays.toString(densities));
0048     // $example off$
0049
0050     jsc.stop();
0051   }
0052 }
0053