[14429] | 1 | #region License Information
|
---|
| 2 | /* HeuristicLab
|
---|
| 3 | * Copyright (C) 2002-2016 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
|
---|
| 4 | *
|
---|
| 5 | * This file is part of HeuristicLab.
|
---|
| 6 | *
|
---|
| 7 | * HeuristicLab is free software: you can redistribute it and/or modify
|
---|
| 8 | * it under the terms of the GNU General Public License as published by
|
---|
| 9 | * the Free Software Foundation, either version 3 of the License, or
|
---|
| 10 | * (at your option) any later version.
|
---|
| 11 | *
|
---|
| 12 | * HeuristicLab is distributed in the hope that it will be useful,
|
---|
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
---|
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
---|
| 15 | * GNU General Public License for more details.
|
---|
| 16 | *
|
---|
| 17 | * You should have received a copy of the GNU General Public License
|
---|
| 18 | * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
|
---|
| 19 | */
|
---|
| 20 | #endregion
|
---|
| 21 |
|
---|
| 22 | using System;
|
---|
| 23 | using System.Collections.Generic;
|
---|
| 24 | using System.Linq;
|
---|
| 25 | using System.Threading;
|
---|
| 26 | using System.Threading.Tasks;
|
---|
| 27 | using HeuristicLab.Common;
|
---|
| 28 | using HeuristicLab.Core;
|
---|
| 29 | using HeuristicLab.Data;
|
---|
| 30 | using HeuristicLab.Parameters;
|
---|
| 31 | using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
|
---|
| 32 |
|
---|
| 33 | namespace HeuristicLab.Optimization.Algorithms.SingleObjective {
|
---|
| 34 | public abstract class HeuristicAlgorithm<TContext, TProblem, TEncoding, TSolution> : Algorithm
|
---|
| 35 | where TContext : HeuristicAlgorithmContext<TProblem, TEncoding, TSolution>,
|
---|
| 36 | IStochasticContext, IEvaluatedSolutionsContext, IBestQualityContext,
|
---|
| 37 | IBestSolutionContext<TSolution>, new()
|
---|
| 38 | where TProblem : class, ISingleObjectiveProblem<TEncoding, TSolution>, ISingleObjectiveProblemDefinition<TEncoding, TSolution>
|
---|
| 39 | where TEncoding : class, IEncoding<TSolution>
|
---|
| 40 | where TSolution : class, ISolution {
|
---|
| 41 | private Type problemType;
|
---|
| 42 |
|
---|
| 43 | public override Type ProblemType {
|
---|
| 44 | get { return typeof(SingleObjectiveProblem<TEncoding, TSolution>); }
|
---|
| 45 | }
|
---|
| 46 |
|
---|
| 47 | public new TProblem Problem {
|
---|
| 48 | get { return (TProblem)base.Problem; }
|
---|
| 49 | set { base.Problem = value; }
|
---|
| 50 | }
|
---|
| 51 |
|
---|
| 52 | private CancellationTokenSource cancellationTokenSource;
|
---|
| 53 | protected CancellationTokenSource CancellationTokenSource {
|
---|
| 54 | get { return cancellationTokenSource; }
|
---|
| 55 | private set { cancellationTokenSource = value; }
|
---|
| 56 | }
|
---|
| 57 |
|
---|
| 58 |
|
---|
| 59 | public int? MaximumEvaluations {
|
---|
| 60 | get {
|
---|
| 61 | var val = ((OptionalValueParameter<IntValue>)Parameters["MaximumEvaluations"]).Value;
|
---|
| 62 | return val != null ? val.Value : (int?)null;
|
---|
| 63 | }
|
---|
| 64 | set {
|
---|
| 65 | var param = (OptionalValueParameter<IntValue>)Parameters["MaximumEvaluations"];
|
---|
| 66 | param.Value = value.HasValue ? new IntValue(value.Value) : null;
|
---|
| 67 | }
|
---|
| 68 | }
|
---|
| 69 |
|
---|
| 70 | public TimeSpan? MaximumExecutionTime {
|
---|
| 71 | get {
|
---|
| 72 | var val = ((OptionalValueParameter<TimeSpanValue>)Parameters["MaximumExecutionTime"]).Value;
|
---|
| 73 | return val != null ? val.Value : (TimeSpan?)null;
|
---|
| 74 | }
|
---|
| 75 | set {
|
---|
| 76 | var param = (OptionalValueParameter<TimeSpanValue>)Parameters["MaximumExecutionTime"];
|
---|
| 77 | param.Value = value.HasValue ? new TimeSpanValue(value.Value) : null;
|
---|
| 78 | }
|
---|
| 79 | }
|
---|
| 80 |
|
---|
| 81 | public double? TargetQuality {
|
---|
| 82 | get {
|
---|
| 83 | var val = ((OptionalValueParameter<DoubleValue>)Parameters["TargetQuality"]).Value;
|
---|
| 84 | return val != null ? val.Value : (double?)null;
|
---|
| 85 | }
|
---|
| 86 | set {
|
---|
| 87 | var param = (OptionalValueParameter<DoubleValue>)Parameters["TargetQuality"];
|
---|
| 88 | param.Value = value.HasValue ? new DoubleValue(value.Value) : null;
|
---|
| 89 | }
|
---|
| 90 | }
|
---|
| 91 |
|
---|
| 92 | public bool SetSeedRandomly {
|
---|
| 93 | get { return ((FixedValueParameter<BoolValue>)Parameters["SetSeedRandomly"]).Value.Value; }
|
---|
| 94 | set { ((FixedValueParameter<BoolValue>)Parameters["SetSeedRandomly"]).Value.Value = value; }
|
---|
| 95 | }
|
---|
| 96 |
|
---|
| 97 | public int Seed {
|
---|
| 98 | get { return ((FixedValueParameter<IntValue>)Parameters["Seed"]).Value.Value; }
|
---|
| 99 | set { ((FixedValueParameter<IntValue>)Parameters["Seed"]).Value.Value = value; }
|
---|
| 100 | }
|
---|
| 101 |
|
---|
| 102 | public IMultiAnalyzer AlgorithmAnalyzer {
|
---|
| 103 | get { return ((ValueParameter<IMultiAnalyzer>)Parameters["Analyzer.Algorithm"]).Value; }
|
---|
| 104 | set { ((ValueParameter<IMultiAnalyzer>)Parameters["Analyzer.Algorithm"]).Value = value; }
|
---|
| 105 | }
|
---|
| 106 |
|
---|
| 107 | public IMultiAnalyzer ProblemAnalyzer {
|
---|
| 108 | get { return ((ValueParameter<IMultiAnalyzer>)Parameters["Analyzer.Problem"]).Value; }
|
---|
| 109 | set { ((ValueParameter<IMultiAnalyzer>)Parameters["Analyzer.Problem"]).Value = value; }
|
---|
| 110 | }
|
---|
| 111 |
|
---|
| 112 | [Storable]
|
---|
| 113 | private ResultCollection results;
|
---|
| 114 | public override ResultCollection Results {
|
---|
| 115 | get { return results; }
|
---|
| 116 | }
|
---|
| 117 |
|
---|
| 118 | [Storable]
|
---|
| 119 | private TContext context;
|
---|
| 120 | public TContext Context {
|
---|
| 121 | get { return context; }
|
---|
| 122 | protected set {
|
---|
| 123 | if (context == value) return;
|
---|
| 124 | context = value;
|
---|
| 125 | }
|
---|
| 126 | }
|
---|
| 127 |
|
---|
| 128 | [StorableConstructor]
|
---|
| 129 | protected HeuristicAlgorithm(bool deserializing) : base(deserializing) { }
|
---|
| 130 | protected HeuristicAlgorithm(HeuristicAlgorithm<TContext, TProblem, TEncoding, TSolution> original, Cloner cloner)
|
---|
| 131 | : base(original, cloner) { }
|
---|
| 132 | protected HeuristicAlgorithm() {
|
---|
| 133 | results = new ResultCollection();
|
---|
| 134 |
|
---|
| 135 | Parameters.Add(new ValueParameter<IMultiAnalyzer>("Analyzer.Algorithm", "The algorithm's analyzers to apply to the solution(s) (independent of the problem)."));
|
---|
| 136 | Parameters.Add(new ValueParameter<IMultiAnalyzer>("Analyzer.Problem", "The problem's analyzer to apply to the solution(s)."));
|
---|
| 137 | Parameters.Add(new OptionalValueParameter<IntValue>("MaximumEvaluations", "The maximum number of solution evaluations."));
|
---|
| 138 | Parameters.Add(new OptionalValueParameter<TimeSpanValue>("MaximumExecutionTime", "The maximum runtime.", new TimeSpanValue(TimeSpan.FromMinutes(1))));
|
---|
| 139 | Parameters.Add(new OptionalValueParameter<DoubleValue>("TargetQuality", "The target quality at which the algorithm terminates."));
|
---|
| 140 | Parameters.Add(new FixedValueParameter<BoolValue>("SetSeedRandomly", "Whether each run of the algorithm should be conducted with a new random seed.", new BoolValue(true)));
|
---|
| 141 | Parameters.Add(new FixedValueParameter<IntValue>("Seed", "The random number seed that is used in case SetSeedRandomly is false.", new IntValue(0)));
|
---|
| 142 |
|
---|
| 143 | }
|
---|
| 144 |
|
---|
| 145 | protected override void OnProblemChanged() {
|
---|
| 146 | base.OnProblemChanged();
|
---|
| 147 | if (ProblemAnalyzer != null) {
|
---|
| 148 | ProblemAnalyzer.Operators.Clear();
|
---|
| 149 | if (Problem != null) {
|
---|
| 150 | foreach (var analyzer in Problem.Operators.OfType<IAnalyzer>()) {
|
---|
| 151 | foreach (var param in analyzer.Parameters.OfType<IScopeTreeLookupParameter>())
|
---|
| 152 | param.Depth = 1;
|
---|
| 153 | ProblemAnalyzer.Operators.Add(analyzer, analyzer.EnabledByDefault);
|
---|
| 154 | }
|
---|
| 155 | }
|
---|
| 156 | }
|
---|
| 157 | }
|
---|
| 158 |
|
---|
| 159 | public override void Prepare() {
|
---|
| 160 | if (Problem == null) return;
|
---|
| 161 | base.Prepare();
|
---|
| 162 | results.Clear();
|
---|
| 163 | Context = null;
|
---|
| 164 | stopRequested = false;
|
---|
| 165 | OnPrepared();
|
---|
| 166 | }
|
---|
| 167 |
|
---|
| 168 | private bool stopRequested = false;
|
---|
| 169 | public override void Start() {
|
---|
| 170 | base.Start();
|
---|
| 171 | CancellationTokenSource = new CancellationTokenSource();
|
---|
| 172 |
|
---|
| 173 | OnStarted();
|
---|
| 174 | var task = Task.Run((Action)Run, cancellationTokenSource.Token);
|
---|
| 175 | var continuation = new Task[3];
|
---|
| 176 | continuation[0] = task.ContinueWith(t => {
|
---|
| 177 | if (t.Exception != null) {
|
---|
| 178 | OnExceptionOccurred(t.Exception.InnerExceptions.Count == 1 ? t.Exception.InnerExceptions[0] : t.Exception);
|
---|
| 179 | }
|
---|
| 180 | OnPaused();
|
---|
| 181 | }, TaskContinuationOptions.OnlyOnFaulted);
|
---|
| 182 | continuation[1] = task.ContinueWith(t => {
|
---|
| 183 | OnStopped();
|
---|
| 184 | }, TaskContinuationOptions.OnlyOnRanToCompletion);
|
---|
| 185 | continuation[2] = task.ContinueWith(t => {
|
---|
| 186 | if (stopRequested) OnStopped();
|
---|
| 187 | else OnPaused();
|
---|
| 188 | }, TaskContinuationOptions.OnlyOnCanceled);
|
---|
| 189 | Task.WhenAny(continuation).ContinueWith(_ => {
|
---|
| 190 | CancellationTokenSource.Dispose();
|
---|
| 191 | CancellationTokenSource = null;
|
---|
| 192 | });
|
---|
| 193 | }
|
---|
| 194 |
|
---|
| 195 | public override void Pause() {
|
---|
| 196 | base.Pause();
|
---|
| 197 | CancellationTokenSource.Cancel();
|
---|
| 198 | }
|
---|
| 199 |
|
---|
| 200 | public override void Stop() {
|
---|
| 201 | // CancellationToken.ThrowIfCancellationRequested() must be called from within the Run method, otherwise stop does nothing
|
---|
| 202 | // alternatively check the IsCancellationRequested property of the cancellation token
|
---|
| 203 | base.Stop();
|
---|
| 204 | stopRequested = true;
|
---|
| 205 | if (CancellationTokenSource != null) {
|
---|
| 206 | try {
|
---|
| 207 | CancellationTokenSource.Cancel();
|
---|
| 208 | } catch {
|
---|
| 209 | OnStopped();
|
---|
| 210 | }
|
---|
| 211 | } else OnStopped();
|
---|
| 212 | }
|
---|
| 213 |
|
---|
| 214 | private DateTime lastUpdateTime;
|
---|
| 215 | private void Run() {
|
---|
| 216 | var token = CancellationTokenSource.Token;
|
---|
| 217 | lastUpdateTime = DateTime.UtcNow;
|
---|
| 218 | System.Timers.Timer timer = new System.Timers.Timer(250);
|
---|
| 219 | timer.AutoReset = true;
|
---|
| 220 | timer.Elapsed += timer_Elapsed;
|
---|
| 221 | timer.Start();
|
---|
| 222 | try {
|
---|
| 223 | if (context == null) {
|
---|
| 224 | context = CreateContext();
|
---|
| 225 |
|
---|
| 226 | IExecutionContext ctxt = null;
|
---|
| 227 | foreach (var item in Problem.ExecutionContextItems)
|
---|
| 228 | ctxt = new Core.ExecutionContext(ctxt, item, Context.Scope);
|
---|
| 229 | ctxt = new Core.ExecutionContext(ctxt, this, Context.Scope);
|
---|
| 230 |
|
---|
| 231 | context.Parent = ctxt;
|
---|
| 232 |
|
---|
| 233 | if (SetSeedRandomly) Seed = new System.Random().Next();
|
---|
| 234 | Context.Random.Reset(Seed);
|
---|
| 235 | Context.Scope.Variables.Add(new Variable("Results", Results));
|
---|
| 236 | } else context.CancellationToken = token;
|
---|
| 237 |
|
---|
| 238 | if (!Context.Initialized) {
|
---|
| 239 | try {
|
---|
| 240 | PerformInitialize(token);
|
---|
| 241 | } catch {
|
---|
| 242 | context = null;
|
---|
| 243 | return;
|
---|
| 244 | }
|
---|
| 245 | Context.Initialized = true;
|
---|
| 246 | }
|
---|
| 247 |
|
---|
| 248 | while (!CheckTerminate(token)) {
|
---|
| 249 | PerformIterate(token);
|
---|
| 250 | PerformAnalyze(token);
|
---|
| 251 | token.ThrowIfCancellationRequested();
|
---|
| 252 | }
|
---|
| 253 | } finally {
|
---|
| 254 | timer.Elapsed -= timer_Elapsed;
|
---|
| 255 | timer.Stop();
|
---|
| 256 | ExecutionTime += DateTime.UtcNow - lastUpdateTime;
|
---|
| 257 | }
|
---|
| 258 | }
|
---|
| 259 |
|
---|
| 260 | protected virtual TContext CreateContext() {
|
---|
| 261 | return new TContext() { Problem = Problem, CancellationToken = CancellationTokenSource.Token };
|
---|
| 262 | }
|
---|
| 263 |
|
---|
| 264 | protected virtual ISingleObjectiveSolutionScope<TSolution> CreateEmptySolutionScope() {
|
---|
| 265 | return new SingleObjectiveSolutionScope<TSolution>(null, Problem.Encoding.Name, double.NaN, Problem.Evaluator.QualityParameter.ActualName);
|
---|
| 266 | }
|
---|
| 267 |
|
---|
| 268 | protected static bool IsBetter(bool maximization, double a, double b) {
|
---|
| 269 | return !double.IsNaN(a) && double.IsNaN(b) || maximization && a > b || !maximization && a < b;
|
---|
| 270 | }
|
---|
| 271 |
|
---|
| 272 | protected virtual void Evaluate(ISingleObjectiveSolutionScope<TSolution> scope, CancellationToken token) {
|
---|
| 273 | scope.Fitness = Problem.Evaluate(scope.Solution, Context.Random);
|
---|
| 274 | }
|
---|
| 275 |
|
---|
| 276 | protected abstract void PerformInitialize(CancellationToken token);
|
---|
| 277 | protected abstract void PerformIterate(CancellationToken token);
|
---|
| 278 | protected virtual void PerformAnalyze(CancellationToken token) {
|
---|
| 279 | IResult res;
|
---|
| 280 | if (!Results.TryGetValue("EvaluatedSolutions", out res)) {
|
---|
| 281 | res = new Result("EvaluatedSolutions", new IntValue(Context.EvaluatedSolutions));
|
---|
| 282 | Results.Add(res);
|
---|
| 283 | } else ((IntValue)res.Value).Value = Context.EvaluatedSolutions;
|
---|
| 284 | if (!Results.TryGetValue("BestQuality", out res)) {
|
---|
| 285 | res = new Result("BestQuality", new DoubleValue(Context.BestQuality));
|
---|
| 286 | Results.Add(res);
|
---|
| 287 | } else ((DoubleValue)res.Value).Value = Context.BestQuality;
|
---|
| 288 |
|
---|
| 289 | RunOperator(ProblemAnalyzer, Context.Scope, token);
|
---|
| 290 | RunOperator(AlgorithmAnalyzer, Context.Scope, token);
|
---|
| 291 | }
|
---|
| 292 |
|
---|
| 293 | protected virtual bool CheckTerminate(CancellationToken token) {
|
---|
| 294 | return MaximumEvaluations.HasValue && Context.EvaluatedSolutions >= MaximumEvaluations.Value
|
---|
| 295 | || MaximumExecutionTime.HasValue && ExecutionTime >= MaximumExecutionTime.Value
|
---|
| 296 | || TargetQuality.HasValue && (Problem.Maximization && Context.BestQuality >= TargetQuality.Value
|
---|
| 297 | || !Problem.Maximization && Context.BestQuality <= TargetQuality.Value);
|
---|
| 298 | }
|
---|
| 299 |
|
---|
| 300 | #region Engine Helper
|
---|
| 301 | protected void RunOperator(IOperator op, IScope scope, CancellationToken cancellationToken) {
|
---|
| 302 | var stack = new Stack<IOperation>();
|
---|
| 303 | stack.Push(Context.CreateChildOperation(op, scope));
|
---|
| 304 |
|
---|
| 305 | while (stack.Count > 0) {
|
---|
| 306 | cancellationToken.ThrowIfCancellationRequested();
|
---|
| 307 |
|
---|
| 308 | var next = stack.Pop();
|
---|
| 309 | if (next is OperationCollection) {
|
---|
| 310 | var coll = (OperationCollection)next;
|
---|
| 311 | for (int i = coll.Count - 1; i >= 0; i--)
|
---|
| 312 | if (coll[i] != null) stack.Push(coll[i]);
|
---|
| 313 | } else if (next is IAtomicOperation) {
|
---|
| 314 | var operation = (IAtomicOperation)next;
|
---|
| 315 | try {
|
---|
| 316 | next = operation.Operator.Execute((IExecutionContext)operation, cancellationToken);
|
---|
| 317 | } catch (Exception ex) {
|
---|
| 318 | stack.Push(operation);
|
---|
| 319 | if (ex is OperationCanceledException) throw ex;
|
---|
| 320 | else throw new OperatorExecutionException(operation.Operator, ex);
|
---|
| 321 | }
|
---|
| 322 | if (next != null) stack.Push(next);
|
---|
| 323 | }
|
---|
| 324 | }
|
---|
| 325 | }
|
---|
| 326 | #endregion
|
---|
| 327 |
|
---|
| 328 | #region Events
|
---|
| 329 | private void timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e) {
|
---|
| 330 | System.Timers.Timer timer = (System.Timers.Timer)sender;
|
---|
| 331 | timer.Enabled = false;
|
---|
| 332 | DateTime now = DateTime.UtcNow;
|
---|
| 333 | ExecutionTime += now - lastUpdateTime;
|
---|
| 334 | lastUpdateTime = now;
|
---|
| 335 | timer.Enabled = true;
|
---|
| 336 | }
|
---|
| 337 | #endregion
|
---|
| 338 | }
|
---|
| 339 | }
|
---|