Пример #1
0
        public void TestSimple()
        {
            int size = 5;

            var heap = new ListHeap <int>(size);

            for (int ai = 0; ai < 10; ai++)
            {
                if (ai < size)
                {
                    Assert.AreEqual(ai, heap.Size());
                }
                else
                {
                    Assert.AreEqual(size, heap.Size());
                }

                heap.Add(ai);
            }

            Assert.AreEqual(0, heap.Extract());
            Assert.AreEqual(4, heap.Size());

            Assert.AreEqual(1, heap.Extract());
            Assert.AreEqual(3, heap.Size());

            Assert.AreEqual(2, heap.Extract());
            Assert.AreEqual(2, heap.Size());

            Assert.AreEqual(3, heap.Extract());
            Assert.AreEqual(1, heap.Size());

            Assert.AreEqual(4, heap.Extract());
            Assert.AreEqual(0, heap.Size());
        }
Пример #2
0
        public void TestSimple() {

            int size = 5;

            var heap = new ListHeap<int>(size);

            for (int ai = 0; ai < 10; ai++) {

                if (ai < size)
                    Assert.AreEqual(ai, heap.Size());
                else
                    Assert.AreEqual(size, heap.Size());

                heap.Add(ai);
            }

            Assert.AreEqual(0, heap.Extract());
            Assert.AreEqual(4, heap.Size());

            Assert.AreEqual(1, heap.Extract());
            Assert.AreEqual(3, heap.Size());

            Assert.AreEqual(2, heap.Extract());
            Assert.AreEqual(2, heap.Size());

            Assert.AreEqual(3, heap.Extract());
            Assert.AreEqual(1, heap.Size());

            Assert.AreEqual(4, heap.Extract());
            Assert.AreEqual(0, heap.Size());


        }
Пример #3
0
        /// <summary>
        /// Finds the n most probable sequences.
        /// </summary>
        /// <param name="numSequences">The number sequences.</param>
        /// <param name="sequence">The sequence.</param>
        /// <param name="additionalContext">The additional context.</param>
        /// <param name="minSequenceScore">The minimum sequence score.</param>
        /// <param name="beamSearch">The beam search.</param>
        /// <param name="validator">The validator.</param>
        public Sequence[] BestSequences(int numSequences, T[] sequence, object[] additionalContext,
                                        double minSequenceScore,
                                        IBeamSearchContextGenerator <T> beamSearch, ISequenceValidator <T> validator)
        {
            IHeap <Sequence> prev = new ListHeap <Sequence>(size);
            IHeap <Sequence> next = new ListHeap <Sequence>(size);

            prev.Add(new Sequence());

            if (additionalContext == null)
            {
                additionalContext = new object[] {}; // EMPTY_ADDITIONAL_CONTEXT
            }

            for (var i = 0; i < sequence.Length; i++)
            {
                var sz = Math.Min(size, prev.Size());

                for (var sc = 0; prev.Size() > 0 && sc < sz; sc++)
                {
                    var top = prev.Extract();

                    var      tmpOutcomes = top.Outcomes;
                    var      outcomes    = tmpOutcomes.ToArray();
                    var      contexts    = beamSearch.GetContext(i, sequence, outcomes, additionalContext);
                    double[] scores;
                    if (contextsCache != null)
                    {
                        scores = (double[])contextsCache.Get(contexts);
                        if (scores == null)
                        {
                            scores = model.Eval(contexts, probs);
                            contextsCache.Put(contexts, scores);
                        }
                    }
                    else
                    {
                        scores = model.Eval(contexts, probs);
                    }

                    var tempScores = new double[scores.Length];
                    for (var c = 0; c < scores.Length; c++)
                    {
                        tempScores[c] = scores[c];
                    }

                    Array.Sort(tempScores);

                    var min = tempScores[Math.Max(0, scores.Length - size)];

                    for (var p = 0; p < scores.Length; p++)
                    {
                        if (scores[p] < min)
                        {
                            continue; //only advance first "size" outcomes
                        }
                        var outcome = model.GetOutcome(p);
                        if (validator.ValidSequence(i, sequence, outcomes, outcome))
                        {
                            var ns = new Sequence(top, outcome, scores[p]);
                            if (ns.Score > minSequenceScore)
                            {
                                next.Add(ns);
                            }
                        }
                    }

                    if (next.Size() == 0)
                    {
                        //if no advanced sequences, advance all valid
                        for (var p = 0; p < scores.Length; p++)
                        {
                            var outcome = model.GetOutcome(p);
                            if (validator.ValidSequence(i, sequence, outcomes, outcome))
                            {
                                var ns = new Sequence(top, outcome, scores[p]);
                                if (ns.Score > minSequenceScore)
                                {
                                    next.Add(ns);
                                }
                            }
                        }
                    }
                }

                // make prev = next; and re-init next (we reuse existing prev set once we clear it)
                prev.Clear();

                var tmp = prev;
                prev = next;
                next = tmp;
            }

            var numSeq       = Math.Min(numSequences, prev.Size());
            var topSequences = new Sequence[numSeq];

            for (var seqIndex = 0; seqIndex < numSeq; seqIndex++)
            {
                topSequences[seqIndex] = prev.Extract();
            }

            return(topSequences);
        }