Java tutorial
/* * Copyright 2007 Tom Gibara * * Licensed 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 com.tomgibara.cluster; import java.io.FileWriter; import java.io.IOException; import java.io.Writer; import org.apache.commons.math.random.GaussianRandomGenerator; import org.apache.commons.math.random.JDKRandomGenerator; import org.apache.commons.math.random.NormalizedRandomGenerator; import org.apache.commons.math.random.UncorrelatedRandomVectorGenerator; public class CreateGaussianCross { public static void main(String[] args) throws IOException { GaussianRandomGenerator gen = new GaussianRandomGenerator(new JDKRandomGenerator()); final double[] center = new double[] { 0, 0 }; int clusterSize = 300; FileWriter writer = new FileWriter("R/cross.txt"); try { writeCluster(gen, center, new double[] { 6, 1 }, clusterSize, writer); writeCluster(gen, center, new double[] { 1, 6 }, clusterSize, writer); } finally { writer.close(); } } private static void writeCluster(NormalizedRandomGenerator gen, double[] means, double[] deviations, int size, Writer writer) throws IOException { UncorrelatedRandomVectorGenerator c = new UncorrelatedRandomVectorGenerator(means, deviations, gen); for (int i = 0; i < size; i++) { double[] pt = c.nextVector(); writer.write(String.format("%3.3f %3.3f%n", pt[0], pt[1])); } } }