| /* |
| * 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.solr.client.solrj.io.eval; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Locale; |
| import java.util.stream.Collectors; |
| import java.util.List; |
| |
| import org.apache.commons.math3.distribution.IntegerDistribution; |
| import org.apache.commons.math3.distribution.MultivariateRealDistribution; |
| import org.apache.commons.math3.distribution.RealDistribution; |
| import org.apache.commons.math3.distribution.MultivariateNormalDistribution; |
| import org.apache.solr.client.solrj.io.stream.expr.StreamExpression; |
| import org.apache.solr.client.solrj.io.stream.expr.StreamFactory; |
| |
| public class SampleEvaluator extends RecursiveObjectEvaluator implements ManyValueWorker { |
| |
| private static final long serialVersionUID = 1; |
| |
| public SampleEvaluator(StreamExpression expression, StreamFactory factory) throws IOException { |
| super(expression, factory); |
| } |
| |
| @Override |
| public Object doWork(Object ... objects) throws IOException{ |
| if(objects.length < 1){ |
| throw new IOException(String.format(Locale.ROOT,"Invalid expression %s - null found for the first value",toExpression(constructingFactory))); |
| } |
| |
| Object first = objects[0]; |
| |
| if(!(first instanceof MultivariateRealDistribution) && !(first instanceof RealDistribution) && !(first instanceof IntegerDistribution) && !(first instanceof MarkovChainEvaluator.MarkovChain)){ |
| throw new IOException(String.format(Locale.ROOT,"Invalid expression %s - found type %s for the first value, expecting a Markov Chain, Real or Integer Distribution",toExpression(constructingFactory), first.getClass().getSimpleName())); |
| } |
| |
| Object second = null; |
| if(objects.length > 1) { |
| second = objects[1]; |
| } |
| |
| if(first instanceof MarkovChainEvaluator.MarkovChain) { |
| MarkovChainEvaluator.MarkovChain markovChain = (MarkovChainEvaluator.MarkovChain)first; |
| if(second != null) { |
| return Arrays.stream(markovChain.sample(((Number) second).intValue())).mapToObj(item -> item).collect(Collectors.toList()); |
| } else { |
| return markovChain.sample(); |
| } |
| } else if (first instanceof RealDistribution) { |
| RealDistribution realDistribution = (RealDistribution) first; |
| if (second != null) { |
| return Arrays.stream(realDistribution.sample(((Number) second).intValue())).mapToObj(item -> item).collect(Collectors.toList()); |
| } else { |
| return realDistribution.sample(); |
| } |
| }else if(first instanceof MultivariateNormalDistribution) { |
| if(second != null) { |
| MultivariateNormalDistribution multivariateNormalDistribution = (MultivariateNormalDistribution)first; |
| int size = ((Number)second).intValue(); |
| double[][] samples = new double[size][]; |
| for(int i=0; i<size; ++i) { |
| samples[i] = multivariateNormalDistribution.sample(); |
| } |
| |
| return new Matrix(samples); |
| } else { |
| MultivariateNormalDistribution multivariateNormalDistribution = (MultivariateNormalDistribution)first; |
| double[] sample = multivariateNormalDistribution.sample(); |
| List<Number> sampleList = new ArrayList<>(sample.length); |
| for(int i=0; i<sample.length; i++) { |
| sampleList.add(sample[i]); |
| } |
| return sampleList; |
| } |
| } else { |
| IntegerDistribution integerDistribution = (IntegerDistribution) first; |
| if(second != null) { |
| return Arrays.stream(integerDistribution.sample(((Number) second).intValue())).mapToObj(item -> item).collect(Collectors.toList()); |
| } else { |
| return integerDistribution.sample(); |
| } |
| } |
| } |
| } |