private KeyValuePair<Fruit, float> CalculateFitness(IEnumerable<Fruit> fruits, Fruit match)
{
var bestFitness = 0.0f;
var mostFitFruit = new Fruit();
foreach (var fruit in fruits) {
var fitness = 0.0f;
if (fruit.Type == match.Type) {
fitness += TypeFit;
}
if (fruit.Color == match.Color) {
fitness += ColorFit;
}
else {
fitness += WeightFit;
}
var c = PercentDeviation(match.Weight, fruit.Weight);
fitness += (1 - c) * WeightFit;
if (!(fitness > bestFitness)) continue;
bestFitness = fitness;
mostFitFruit = fruit;
}
RemoveFromSupply(mostFitFruit);
return new KeyValuePair<Fruit, float>(mostFitFruit, bestFitness * 100);
}
public KeyValuePair<Fruit, float> PickFruit(IEnumerable<Fruit> fruits, Fruit match)
{
var picked =
fruits.Where(x => x.Type == match.Type).Where(y => y.Color == match.Color).FirstOrDefault(z => z.Weight == match.Weight);
if (picked == null) return new KeyValuePair<Fruit, float>(null, 0);
RemoveFromSupply(picked);
return new KeyValuePair<Fruit, float>(picked, 100);
}
public IEnumerable<Fruit> Provide(int howMany)
{
var random = new Random();
var fruitArray = Enum.GetValues(typeof(FruitType));
var colorArray = Enum.GetValues(typeof(FruitColor));
for (var i = 0; i < howMany; i++) {
var fruit = new Fruit(
(FruitType)fruitArray.GetValue(random.Next(1, fruitArray.Length)),
(FruitColor)fruitArray.GetValue(random.Next(1, colorArray.Length)),
random.Next(50, 500));
yield return fruit;
}
}
public void RemoveFromSupply(Fruit match)
{
using (var dbContext = _dbHandler as FruitMachineDbContext)
{
if (dbContext != null)
{
var result = from f in dbContext.Fruits where f.FruitId == match.FruitId select f;
if (result.Any())
{
var f = result.First();
dbContext.Fruits.Remove(f);
dbContext.SaveChanges();
}
}
}
}
/// <summary>
/// Matches existing fruit objects against list of criteria
/// Match priority: Type 70%, Color 20%, Weight 10%
/// </summary>
/// <param name="fruits">Collection of Fruit objects to test against</param>
/// <param name="match">Fruit object with the exact criteria to match</param>
/// <returns></returns>
public KeyValuePair<Fruit, float> PickFruit(IEnumerable<Fruit> fruits, Fruit match)
{
return CalculateFitness(fruits, match);
}
public void PrintResult(Fruit fruit, float fitness)
{
Console.WriteLine("This came close: ");
Console.WriteLine(fruit);
Console.WriteLine("With a fitness of " + fitness);
}
