Exemplo n.º 1
0
        private float DecodeOutput(string[] OutputSentence, IComputeGraph g, float cost, SparseWeightMatrix sparseInput, List <WeightMatrix> encoded, AttentionDecoder decoder, WeightMatrix Whd, WeightMatrix bd, WeightMatrix Embedding)
        {
            int ix_input = (int)SENTTAGS.START;

            for (int i = 0; i < OutputSentence.Length + 1; i++)
            {
                int ix_target = (int)SENTTAGS.UNK;
                if (i == OutputSentence.Length)
                {
                    ix_target = (int)SENTTAGS.END;
                }
                else
                {
                    if (t_wordToIndex.ContainsKey(OutputSentence[i]))
                    {
                        ix_target = t_wordToIndex[OutputSentence[i]];
                    }
                }


                var x       = g.PeekRow(Embedding, ix_input);
                var eOutput = decoder.Decode(sparseInput, x, encoded, g);
                if (UseDropout)
                {
                    eOutput = g.Dropout(eOutput, 0.2f);
                }
                var o = g.muladd(eOutput, Whd, bd);
                if (UseDropout)
                {
                    o = g.Dropout(o, 0.2f);
                }

                var probs = g.SoftmaxWithCrossEntropy(o);
                cost += (float)-Math.Log(probs.Weight[ix_target]);

                o.Gradient             = probs.Weight;
                o.Gradient[ix_target] -= 1;
                ix_input = ix_target;
            }
            return(cost);
        }