public static IList <ConstructiveResult> SolveWithPerformanceTest(IList <KnapsackInstance> instances, ConstructiveStrategy strategy, CommandLineOptions options)
{
PreparePerformanceTest(instances, strategy);
var stopWatch = new Stopwatch();
var results = new List <ConstructiveResult>();
foreach (var instance in instances)
{
Console.WriteLine($"Processing instance no. {instance.Id}");
ConstructiveResult result = null;
//The algorithm must run repeat at least the set amount of times;
for (int i = 0; i < REPEAT_COUNT; i++)
{
GC.Collect();
GC.WaitForPendingFinalizers();
//GC.TryStartNoGCRegion(200000000);
stopWatch.Start();
result = strategy.Solve(instance);
stopWatch.Stop();
strategy.FreeAll();
//GC.EndNoGCRegion();
}
var averageRuntime = stopWatch.Elapsed.TotalMilliseconds / REPEAT_COUNT;
//Save only the last result
if (result != null)
{
result.DataSetName = options.DataSetName;
result.RunTimeMs = averageRuntime;
if (result.Strategy == null)
{
result.Strategy = options.Strategy;
}
results.Add(result);
}
stopWatch.Reset();
}
return(results);
}
public override ConstructiveResult Solve(KnapsackInstance instance)
{
BestConfiguration = new KnapsackConfiguration {
Price = int.MinValue, Weight = 0, ItemVector = CreateEmptySolution(instance.ItemCount)
};
FindBestConfiguration(0, new KnapsackConfiguration {
Price = 0, Weight = 0, ItemVector = new List <bool>()
}, instance.GetPriceOfAllItems(), instance);
var result = new ConstructiveResult
{
KnapsackInstance = instance,
NumberOfSteps = numberOfSteps,
Configuration = BestConfiguration
};
return(result);
}
public override ConstructiveResult Solve(KnapsackInstance instance)
{
BestConfiguration = new KnapsackConfiguration {
Price = int.MinValue, Weight = 0, ItemVector = new List <bool>()
};
numberOfSteps = 0;
FindBestConfiguration(0, new KnapsackConfiguration {
Price = 0, Weight = 0, ItemVector = new List <bool>()
}, instance);
var result = new ConstructiveResult
{
KnapsackInstance = instance,
NumberOfSteps = numberOfSteps,
Configuration = BestConfiguration
};
return(result);
}
public static bool ConstructiveComparator(ConstructiveResult result, KnapsackReferenceSolution referenceSolution)
{
//Calculate and save epsilon
var optimalPrice = referenceSolution.Price;
var actualPrice = result.Configuration.Price;
if (Math.Max(actualPrice, optimalPrice) == 0)
{
result.Epsilon = 0;
}
else
{
result.Epsilon = (float)Math.Abs(actualPrice - optimalPrice) / Math.Max(actualPrice, optimalPrice);
}
if (result.Configuration.Price != referenceSolution.Price || result.Configuration.Weight > result.KnapsackInstance.KnapsackSize)
{
Console.WriteLine($"Permutation instance solution (id {result.KnapsackInstance.Id}) incorrect," +
$" result: {OutputWriter.ItemVectorToString(result.Configuration.ItemVector)} (price {result.Configuration.Price})" +
$" expected result: {OutputWriter.ItemVectorToString(referenceSolution.ItemVector)} (price {referenceSolution.Price})");
return(false);
}
return(true);
}