public override string[] draw(String[] cards, int drawn, String[] blockers, List <Draw> drawList)
{
return(DrawPrediction.getDrawingHand(drawList, cards, drawn, true, blockers));
}
/// <summary>
/// get the best drawing hand for the given hand, number drawn and hand valuation. optionally returns score of all possible drawing hands.
/// </summary>
/// <param name="list"></param>
/// <param name="hand"></param>
/// <param name="drawn"></param>
/// <param name="high"></param>
/// <param name="blockers"></param>
/// <returns></returns>
public static String[] getDrawingHand(List <Draw> list, String[] hand, int drawn, bool high, String[] blockers)
{
if (hand.Length > 5)
{
throw new ArgumentException("invalid hand: " + (string.Join(", ", hand)));
}
// XXX really should take into account multiple draws
// but thats only really a problem if you draw a greater number on a
// later street (which is a bad strategy and almost unheard of)
// e.g. draw 1, 1, 5 - obviously can't use final hand to predict any of them
// related problem is that a later hand might contain blockers from a
// reshuffle and so can't possibly occur on an earlier street
// and you might not even have enough cards that aren't blocked,
// i.e. bincoff(length(hand - blockers), 5 - drawn) needs to be >= 1
if (blockers != null && blockers.Length > 0)
{
String[] hand2 = ArrayUtil.sub(hand, blockers);
if (hand2.Length != hand.Length)
{
// some of the cards were blocked
// cheat and increase the draw amount (if necessary)
drawn = Math.Max(5 - hand2.Length, drawn);
hand = hand2;
}
}
BigInteger combs = MathsUtil.binomialCoefficient(hand.Length, 5 - drawn);
if ((int)combs <= 0)
{
throw new ArgumentException("invalid combs: " + combs);
}
// XXX if only 1 comb, just return hand?
// high draw works best with around 0.9, low draw with 0.99
// generally, you can win in high with any top 10% hand, but low draw
// pretty much needs 7-high (75432, 76432, 76542, etc) to win
// XXX actually it probably depends if it's 2-7 single or triple draw
double bias = high ? 0.9 : 0.99;
OmahaValue value;
if (high)
{
value = new HiValue();
}
else
{
value = new DsLowValue();
}
if (drawn < 0 || drawn > 5)
{
throw new ArgumentException("invalid drawn: " + drawn);
}
else if (drawn == 5)
{
// special case, no draw and no meaningful score
return(new String[0]);
}
else if (drawn == 0)
{
// special case, nothing to test other than given hand
if (list != null)
{
float s = score(value.value(hand), bias);
list.Add(new Draw(hand, s));
}
return(hand.ToArray());
}
// drawing 1-4
// from players point of view, all other cards are possible (even the blockers)
String[] deck = OmahaPoker.remdeck(null, hand);
String[] drawnHand = new String[5];
int imax = MathsUtil.binomialCoefficientFast(hand.Length, 5 - drawn);
int jmax = MathsUtil.binomialCoefficientFast(deck.Length, drawn);
String[] maxDrawingHand = null;
float maxScore = -1f;
for (int i = 0; i < imax; i++)
{
ArrayUtil.Populate(drawnHand, null);
// pick kept from hand
MathsUtil.kCombination(5 - drawn, i, hand, drawnHand, 0);
//System.out.println("drawnHand: " + Arrays.toString(drawnHand));
float score = 0;
for (int j = 0; j < jmax; j++)
{
// pick drawn from deck
MathsUtil.kCombination(drawn, j, deck, drawnHand, 5 - drawn);
//System.out.println(" drawnHand: " + Arrays.toString(drawnHand));
int v = value.value(drawnHand);
score += DrawPrediction.score(v, bias);
}
float averageScore = score / (1.0f * jmax);
string[] drawingHand = drawnHand.Take(5 - drawn).ToArray();
if (list != null)
{
Array.Sort(drawingHand, Cmp.revCardCmp);
list.Add(new Draw(drawingHand, averageScore));
}
if (score > maxScore)
{
// copy new max hole cards
maxDrawingHand = drawingHand;
maxScore = score;
}
}
if (list != null)
{
list.Sort();
list.Reverse();
}
return(maxDrawingHand);
}
