package edu.stanford.nlp.ie.crf; import edu.stanford.nlp.util.logging.Redwood; import edu.stanford.nlp.math.ArrayMath; import edu.stanford.nlp.optimization.AbstractCachingDiffFunction; import edu.stanford.nlp.sequences.SeqClassifierFlags; import edu.stanford.nlp.util.Index; import edu.stanford.nlp.util.Quadruple; import java.util.*; /** * @author Mengqiu Wang */ public class CRFNonLinearSecondOrderLogConditionalObjectiveFunction extends AbstractCachingDiffFunction implements HasCliquePotentialFunction { /** A logger for this class */ private static Redwood.RedwoodChannels log = Redwood.channels(CRFNonLinearSecondOrderLogConditionalObjectiveFunction.class); public static final int NO_PRIOR = 0; public static final int QUADRATIC_PRIOR = 1; /* Use a Huber robust regression penalty (L1 except very near 0) not L2 */ public static final int HUBER_PRIOR = 2; public static final int QUARTIC_PRIOR = 3; boolean useOutputLayer; boolean useHiddenLayer; boolean useSigmoid; SeqClassifierFlags flags; int count = 0; protected int prior; protected double sigma; protected double epsilon; Random random = new Random(2147483647L); /** label indices - for all possible label sequences - for each feature */ List<Index<CRFLabel>> labelIndices; Index<String> classIndex; // didn't have <String> before. Added since that's what is assumed everywhere. double[][] Ehat; // empirical counts of all the linear features [feature][class] double[][] Uhat; // empirical counts of all the output layer features [num of class][input layer size] double[][] What; // empirical counts of all the input layer features [input layer size][featureIndex.size()] int window; int numClasses; // hidden layer number of neuron = numHiddenUnits * numClasses int numHiddenUnits; int[] map; int[][][][] data; // data[docIndex][tokenIndex][][] int[][] docWindowLabels; int[][] labels; // labels[docIndex][tokenIndex] int domainDimension = -1; int inputLayerSize = -1; int outputLayerSize = -1; int inputLayerSize4Edge= -1; int outputLayerSize4Edge = -1; int edgeParamCount = -1; int numNodeFeatures = -1; int numEdgeFeatures = -1; int beforeOutputWeights = -1; // for debugging int originalFeatureCount = -1; int[][] weightIndices; String crfType = "maxent"; String backgroundSymbol; public static boolean VERBOSE = false; public static int getPriorType(String priorTypeStr) { if (priorTypeStr == null) return QUADRATIC_PRIOR; // default if ("QUADRATIC".equalsIgnoreCase(priorTypeStr)) { return QUADRATIC_PRIOR; } else if ("HUBER".equalsIgnoreCase(priorTypeStr)) { return HUBER_PRIOR; } else if ("QUARTIC".equalsIgnoreCase(priorTypeStr)) { return QUARTIC_PRIOR; } else if (priorTypeStr.equalsIgnoreCase("NONE")) { return NO_PRIOR; } else { throw new IllegalArgumentException("Unknown prior type: " + priorTypeStr); } } CRFNonLinearSecondOrderLogConditionalObjectiveFunction(int[][][][] data, int[][] labels, int window, Index classIndex, List<Index<CRFLabel>> labelIndices, int[] map, SeqClassifierFlags flags, int numNodeFeatures, int numEdgeFeatures) { this(data, labels, window, classIndex, labelIndices, map, QUADRATIC_PRIOR, flags, numNodeFeatures, numEdgeFeatures); } CRFNonLinearSecondOrderLogConditionalObjectiveFunction(int[][][][] data, int[][] labels, int window, Index<String> classIndex, List<Index<CRFLabel>> labelIndices, int[] map, int prior, SeqClassifierFlags flags, int numNodeFeatures, int numEdgeFeatures) { this.window = window; this.classIndex = classIndex; this.numClasses = classIndex.size(); this.labelIndices = labelIndices; this.data = data; this.flags = flags; this.map = map; this.labels = labels; this.prior = prior; this.backgroundSymbol = flags.backgroundSymbol; this.sigma = flags.sigma; this.outputLayerSize = numClasses; this.outputLayerSize4Edge = numClasses * numClasses; this.numHiddenUnits = flags.numHiddenUnits; this.inputLayerSize = numHiddenUnits * numClasses; this.inputLayerSize4Edge = numHiddenUnits * numClasses * numClasses; this.numNodeFeatures = numNodeFeatures; this.numEdgeFeatures = numEdgeFeatures; this.useOutputLayer = flags.useOutputLayer; this.useHiddenLayer = flags.useHiddenLayer; this.useSigmoid = flags.useSigmoid; this.docWindowLabels = new int[data.length][]; if (!useOutputLayer) { log.info("Output layer not activated, inputLayerSize must be equal to numClasses, setting it to " + numClasses); this.inputLayerSize = numClasses; this.inputLayerSize4Edge = numClasses * numClasses; } else if (flags.softmaxOutputLayer && !(flags.sparseOutputLayer || flags.tieOutputLayer)) { throw new RuntimeException("flags.softmaxOutputLayer == true, but neither flags.sparseOutputLayer or flags.tieOutputLayer is true"); } // empiricalCounts(); } @Override public int domainDimension() { if (domainDimension < 0) { originalFeatureCount = 0; for (int aMap : map) { int s = labelIndices.get(aMap).size(); originalFeatureCount += s; } domainDimension = 0; domainDimension += inputLayerSize4Edge * numEdgeFeatures; domainDimension += inputLayerSize * numNodeFeatures; beforeOutputWeights = domainDimension; if (useOutputLayer) { if (flags.sparseOutputLayer) { domainDimension += outputLayerSize4Edge * numHiddenUnits; domainDimension += outputLayerSize * numHiddenUnits; } else if (flags.tieOutputLayer) { domainDimension += 1 * numHiddenUnits; domainDimension += 1 * numHiddenUnits; } else { domainDimension += outputLayerSize4Edge * inputLayerSize4Edge; domainDimension += outputLayerSize * inputLayerSize; } } log.info("originalFeatureCount: "+originalFeatureCount); log.info("beforeOutputWeights: "+beforeOutputWeights); log.info("domainDimension: "+domainDimension); } return domainDimension; } @Override public double[] initial() { double[] initial = new double[domainDimension()]; // randomly initialize weights if (useHiddenLayer || useOutputLayer) { double epsilon = 0.1; double twoEpsilon = epsilon * 2; int count = 0; double val = 0; if (flags.blockInitialize) { int interval4Edge = numEdgeFeatures / numHiddenUnits; for (int i = 0; i < numHiddenUnits; i++) { int lower = i * interval4Edge; int upper = (i + 1) * interval4Edge; if (i == numHiddenUnits - 1) upper = numEdgeFeatures; for (int j = 0; j < outputLayerSize4Edge; j++) { for (int k = 0; k < numEdgeFeatures; k++) { val = 0; if (k >= lower && k < upper) { val = random.nextDouble() * twoEpsilon - epsilon; } initial[count++] = val; } } } int interval = numNodeFeatures / numHiddenUnits; for (int i = 0; i < numHiddenUnits; i++) { int lower = i * interval; int upper = (i + 1) * interval; if (i == numHiddenUnits - 1) upper = numNodeFeatures; for (int j = 0; j < outputLayerSize; j++) { for (int k = 0; k < numNodeFeatures; k++) { val = 0; if (k >= lower && k < upper) { val = random.nextDouble() * twoEpsilon - epsilon; } initial[count++] = val; } } } if (count != beforeOutputWeights) { throw new RuntimeException("after blockInitialize, param Index (" + count + ") not equal to beforeOutputWeights (" + beforeOutputWeights + ")"); } } else { for (int i = 0; i < beforeOutputWeights; i++) { val = random.nextDouble() * twoEpsilon - epsilon; initial[count++] = val; } } if (flags.sparseOutputLayer) { for (int i = 0; i < outputLayerSize4Edge; i++) { double total = 1; for (int j = 0; j < numHiddenUnits-1; j++) { val = random.nextDouble() * total; initial[count++] = val; total -= val; } initial[count++] = total; } for (int i = 0; i < outputLayerSize; i++) { double total = 1; for (int j = 0; j < numHiddenUnits-1; j++) { val = random.nextDouble() * total; initial[count++] = val; total -= val; } initial[count++] = total; } } else if (flags.tieOutputLayer) { double total = 1; double sum = 0; for (int j = 0; j < numHiddenUnits-1; j++) { val = random.nextDouble() * total; initial[count++] = val; total -= val; } initial[count++] = total; total = 1; sum = 0; for (int j = 0; j < numHiddenUnits-1; j++) { val = random.nextDouble() * total; initial[count++] = val; total -= val; } initial[count++] = total; } else { for (int i = beforeOutputWeights; i < domainDimension(); i++) { val = random.nextDouble() * twoEpsilon - epsilon; initial[count++] = val; } } if (count != domainDimension()) { throw new RuntimeException("after param initialization, param Index (" + count + ") not equal to domainDimension (" + domainDimension() + ")"); } } return initial; } private double[][] emptyU4Edge() { int innerSize = inputLayerSize4Edge; if (flags.sparseOutputLayer || flags.tieOutputLayer) { innerSize = numHiddenUnits; } int outerSize = outputLayerSize4Edge; if (flags.tieOutputLayer) { outerSize = 1; } double[][] temp = new double[outerSize][innerSize]; for (int i = 0; i < outerSize; i++) { temp[i] = new double[innerSize]; } return temp; } private double[][] emptyW4Edge() { double[][] temp = new double[inputLayerSize4Edge][numEdgeFeatures]; for (int i = 0; i < inputLayerSize; i++) { temp[i] = new double[numEdgeFeatures]; } return temp; } private double[][] emptyU() { int innerSize = inputLayerSize; if (flags.sparseOutputLayer || flags.tieOutputLayer) { innerSize = numHiddenUnits; } int outerSize = outputLayerSize; if (flags.tieOutputLayer) { outerSize = 1; } double[][] temp = new double[outerSize][innerSize]; for (int i = 0; i < outerSize; i++) { temp[i] = new double[innerSize]; } return temp; } private double[][] emptyW() { double[][] temp = new double[inputLayerSize][numNodeFeatures]; for (int i = 0; i < inputLayerSize; i++) { temp[i] = new double[numNodeFeatures]; } return temp; } public Quadruple<double[][], double[][], double[][], double[][]> separateWeights(double[] x) { int index = 0; double[][] inputLayerWeights4Edge = emptyW4Edge(); for (int i = 0; i < inputLayerWeights4Edge.length; i++) { for (int j = 0; j < inputLayerWeights4Edge[i].length; j++) { inputLayerWeights4Edge[i][j] = x[index++]; } } double[][] inputLayerWeights = emptyW(); for (int i = 0; i < inputLayerWeights.length; i++) { for (int j = 0; j < inputLayerWeights[i].length; j++) { inputLayerWeights[i][j] = x[index++]; } } double[][] outputLayerWeights4Edge = emptyU4Edge(); for (int i = 0; i < outputLayerWeights4Edge.length; i++) { for (int j = 0; j < outputLayerWeights4Edge[i].length; j++) { if (useOutputLayer) outputLayerWeights4Edge[i][j] = x[index++]; else outputLayerWeights4Edge[i][j] = 1; } } double[][] outputLayerWeights = emptyU(); for (int i = 0; i < outputLayerWeights.length; i++) { for (int j = 0; j < outputLayerWeights[i].length; j++) { if (useOutputLayer) outputLayerWeights[i][j] = x[index++]; else outputLayerWeights[i][j] = 1; } } assert(index == x.length); return new Quadruple<>(inputLayerWeights4Edge, outputLayerWeights4Edge, inputLayerWeights, outputLayerWeights); } public CliquePotentialFunction getCliquePotentialFunction(double[] x) { Quadruple<double[][], double[][], double[][], double[][]> allParams = separateWeights(x); double[][] W4Edge = allParams.first(); // inputLayerWeights4Edge double[][] U4Edge = allParams.second(); // outputLayerWeights4Edge double[][] W = allParams.third(); // inputLayerWeights double[][] U = allParams.fourth(); // outputLayerWeights return new NonLinearSecondOrderCliquePotentialFunction(W4Edge, U4Edge, W, U, flags); } // todo [cdm]: Below data[m] --> docData /** * Calculates both value and partial derivatives at the point x, and save them internally. */ @Override public void calculate(double[] x) { double prob = 0.0; // the log prob of the sequence given the model, which is the negation of value at this point Quadruple<double[][], double[][], double[][], double[][]> allParams = separateWeights(x); double[][] W4Edge = allParams.first(); // inputLayerWeights4Edge double[][] U4Edge = allParams.second(); // outputLayerWeights4Edge double[][] W = allParams.third(); // inputLayerWeights double[][] U = allParams.fourth(); // outputLayerWeights double[][] Y4Edge = null; double[][] Y = null; if (flags.softmaxOutputLayer) { Y4Edge = new double[U4Edge.length][]; for (int i = 0; i < U4Edge.length; i++) { Y4Edge[i] = ArrayMath.softmax(U4Edge[i]); } Y = new double[U.length][]; for (int i = 0; i < U.length; i++) { Y[i] = ArrayMath.softmax(U[i]); } } double[][] What4Edge = emptyW4Edge(); double[][] Uhat4Edge = emptyU4Edge(); double[][] What = emptyW(); double[][] Uhat = emptyU(); // the expectations over counts // first index is feature index, second index is of possible labeling double[][] eW4Edge = emptyW4Edge(); double[][] eU4Edge = emptyU4Edge(); double[][] eW = emptyW(); double[][] eU = emptyU(); // iterate over all the documents for (int m = 0; m < data.length; m++) { int[][][] docData = data[m]; int[] docLabels = labels[m]; NonLinearSecondOrderCliquePotentialFunction cliquePotentialFunction = new NonLinearSecondOrderCliquePotentialFunction(W4Edge, U4Edge, W, U, flags); // make a clique tree for this document CRFCliqueTree cliqueTree = CRFCliqueTree.getCalibratedCliqueTree(docData, labelIndices, numClasses, classIndex, backgroundSymbol, cliquePotentialFunction, null); // compute the log probability of the document given the model with the parameters x int[] given = new int[window - 1]; Arrays.fill(given, classIndex.indexOf(backgroundSymbol)); int[] windowLabels = new int[window]; Arrays.fill(windowLabels, classIndex.indexOf(backgroundSymbol)); if (docLabels.length>docData.length) { // only true for self-training // fill the given array with the extra docLabels System.arraycopy(docLabels, 0, given, 0, given.length); System.arraycopy(docLabels, 0, windowLabels, 0, windowLabels.length); // shift the docLabels array left int[] newDocLabels = new int[docData.length]; System.arraycopy(docLabels, docLabels.length-newDocLabels.length, newDocLabels, 0, newDocLabels.length); docLabels = newDocLabels; } // iterate over the positions in this document for (int i = 0; i < docData.length; i++) { int label = docLabels[i]; double p = cliqueTree.condLogProbGivenPrevious(i, label, given); if (VERBOSE) { log.info("P(" + label + "|" + ArrayMath.toString(given) + ")=" + p); } prob += p; System.arraycopy(given, 1, given, 0, given.length - 1); given[given.length - 1] = label; } // compute the expected counts for this document, which we will need to compute the derivative // iterate over the positions in this document for (int i = 0; i < docData.length; i++) { // for each possible clique at this position System.arraycopy(windowLabels, 1, windowLabels, 0, window - 1); windowLabels[window - 1] = docLabels[i]; for (int j = 0; j < docData[i].length; j++) { Index<CRFLabel> labelIndex = labelIndices.get(j); // for each possible labeling for that clique int[] cliqueFeatures = docData[i][j]; double[] As = null; double[] fDeriv = null; double[][] yTimesA = null; double[] sumOfYTimesA = null; int inputSize, outputSize = -1; if (j == 0) { inputSize = inputLayerSize; outputSize = outputLayerSize; As = cliquePotentialFunction.hiddenLayerOutput(W, cliqueFeatures, flags, null, j+1); } else { inputSize = inputLayerSize4Edge; outputSize = outputLayerSize4Edge; As = cliquePotentialFunction.hiddenLayerOutput(W4Edge, cliqueFeatures, flags, null, j+1); } fDeriv = new double[inputSize]; double fD = 0; for (int q = 0; q < inputSize; q++) { if (useSigmoid) { fD = As[q] * (1 - As[q]); } else { fD = 1 - As[q] * As[q]; } fDeriv[q] = fD; } // calculating yTimesA for softmax if (flags.softmaxOutputLayer) { double val = 0; yTimesA = new double[outputSize][numHiddenUnits]; for (int ii = 0; ii < outputSize; ii++) { yTimesA[ii] = new double[numHiddenUnits]; } sumOfYTimesA = new double[outputSize]; for (int k = 0; k < outputSize; k++) { double[] Yk = null; if (flags.tieOutputLayer) { if (j == 0) { Yk = Y[0]; } else { Yk = Y4Edge[0]; } } else { if (j == 0) { Yk = Y[k]; } else { Yk = Y4Edge[k]; } } double sum = 0; for (int q = 0; q < inputSize; q++) { if (q % outputSize == k) { int hiddenUnitNo = q / outputSize; val = As[q] * Yk[hiddenUnitNo]; yTimesA[k][hiddenUnitNo] = val; sum += val; } } sumOfYTimesA[k] = sum; } } // calculating Uhat What int[] cliqueLabel = new int[j + 1]; System.arraycopy(windowLabels, window - 1 - j, cliqueLabel, 0, j + 1); CRFLabel crfLabel = new CRFLabel(cliqueLabel); int givenLabelIndex = labelIndex.indexOf(crfLabel); double[] Uk = null; double[] UhatK = null; double[] Yk = null; double[] yTimesAK = null; double sumOfYTimesAK = 0; if (flags.tieOutputLayer) { if (j == 0) { Uk = U[0]; UhatK = Uhat[0]; } else { Uk = U4Edge[0]; UhatK = Uhat4Edge[0]; } if (flags.softmaxOutputLayer) { if (j == 0) { Yk = Y[0]; } else { Yk = Y4Edge[0]; } } } else { if (j == 0) { Uk = U[givenLabelIndex]; UhatK = Uhat[givenLabelIndex]; } else { Uk = U4Edge[givenLabelIndex]; UhatK = Uhat4Edge[givenLabelIndex]; } if (flags.softmaxOutputLayer) { if (j == 0) { Yk = Y[givenLabelIndex]; } else { Yk = Y4Edge[givenLabelIndex]; } } } if (flags.softmaxOutputLayer) { yTimesAK = yTimesA[givenLabelIndex]; sumOfYTimesAK = sumOfYTimesA[givenLabelIndex]; } for (int k = 0; k < inputSize; k++) { double deltaK = 1; if (flags.sparseOutputLayer || flags.tieOutputLayer) { if (k % outputSize == givenLabelIndex) { int hiddenUnitNo = k / outputSize; if (flags.softmaxOutputLayer) { UhatK[hiddenUnitNo] += (yTimesAK[hiddenUnitNo] - Yk[hiddenUnitNo] * sumOfYTimesAK); deltaK *= Yk[hiddenUnitNo]; } else { UhatK[hiddenUnitNo] += As[k]; deltaK *= Uk[hiddenUnitNo]; } } } else { UhatK[k] += As[k]; if (useOutputLayer) { deltaK *= Uk[k]; } } if (useHiddenLayer) deltaK *= fDeriv[k]; if (useOutputLayer) { if (flags.sparseOutputLayer || flags.tieOutputLayer) { if (k % outputSize == givenLabelIndex) { double[] WhatK = null; if (j == 0) { WhatK = What[k]; } else { WhatK = What4Edge[k]; } for (int cliqueFeature : cliqueFeatures) { WhatK[cliqueFeature] += deltaK; } } } else { double[] WhatK = null; if (j == 0) { WhatK = What[k]; } else { WhatK = What4Edge[k]; } for (int cliqueFeature : cliqueFeatures) { WhatK[cliqueFeature] += deltaK; } } } else { if (k == givenLabelIndex) { double[] WhatK = null; if (j == 0) { WhatK = What[k]; } else { WhatK = What4Edge[k]; } for (int cliqueFeature : cliqueFeatures) { WhatK[cliqueFeature] += deltaK; } } } } for (int k = 0; k < labelIndex.size(); k++) { // labelIndex.size() == numClasses int[] label = labelIndex.get(k).getLabel(); double p = cliqueTree.prob(i, label); // probability of these labels occurring in this clique with these features double[] Uk2 = null; double[] eUK = null; double[] Yk2 = null; if (flags.tieOutputLayer) { if (j == 0) { // for node features Uk2 = U[0]; eUK = eU[0]; } else { Uk2 = U4Edge[0]; eUK = eU4Edge[0]; } if (flags.softmaxOutputLayer) { if (j == 0) { Yk2 = Y[0]; } else { Yk2 = Y4Edge[0]; } } } else { if (j == 0) { Uk2 = U[k]; eUK = eU[k]; } else { Uk2 = U4Edge[k]; eUK = eU4Edge[k]; } if (flags.softmaxOutputLayer) { if (j == 0) { Yk2 = Y[k]; } else { Yk2 = Y4Edge[k]; } } } if (useOutputLayer) { for (int q = 0; q < inputSize; q++) { double deltaQ = 1; if (flags.sparseOutputLayer || flags.tieOutputLayer) { if (q % outputSize == k) { int hiddenUnitNo = q / outputSize; if (flags.softmaxOutputLayer) { eUK[hiddenUnitNo] += (yTimesA[k][hiddenUnitNo] - Yk2[hiddenUnitNo] * sumOfYTimesA[k]) * p; deltaQ = Yk2[hiddenUnitNo]; } else { eUK[hiddenUnitNo] += As[q] * p; deltaQ = Uk2[hiddenUnitNo]; } } } else { eUK[q] += As[q] * p; deltaQ = Uk2[q]; } if (useHiddenLayer) deltaQ *= fDeriv[q]; if (flags.sparseOutputLayer || flags.tieOutputLayer) { if (q % outputSize == k) { double[] eWq = null; if (j == 0) { eWq = eW[q]; } else { eWq = eW4Edge[q]; } for (int cliqueFeature : cliqueFeatures) { eWq[cliqueFeature] += deltaQ * p; } } } else { double[] eWq = null; if (j == 0) { eWq = eW[q]; } else { eWq = eW4Edge[q]; } for (int cliqueFeature : cliqueFeatures) { eWq[cliqueFeature] += deltaQ * p; } } } } else { double deltaK = 1; if (useHiddenLayer) deltaK *= fDeriv[k]; double[] eWK = null; if (j == 0) { eWK = eW[k]; } else { eWK = eW4Edge[k]; } for (int cliqueFeature : cliqueFeatures) { eWK[cliqueFeature] += deltaK * p; } } } } } } if (Double.isNaN(prob)) { // shouldn't be the case throw new RuntimeException("Got NaN for prob in CRFNonLinearSecondOrderLogConditionalObjectiveFunction.calculate()"); } value = -prob; if(VERBOSE){ log.info("value is " + value); } // compute the partial derivative for each feature by comparing expected counts to empirical counts int index = 0; for (int i = 0; i < eW4Edge.length; i++) { for (int j = 0; j < eW4Edge[i].length; j++) { derivative[index++] = (eW4Edge[i][j] - What4Edge[i][j]); if (VERBOSE) { log.info("inputLayerWeights4Edge deriv(" + i + "," + j + ") = " + eW4Edge[i][j] + " - " + What4Edge[i][j] + " = " + derivative[index - 1]); } } } for (int i = 0; i < eW.length; i++) { for (int j = 0; j < eW[i].length; j++) { derivative[index++] = (eW[i][j] - What[i][j]); if (VERBOSE) { log.info("inputLayerWeights deriv(" + i + "," + j + ") = " + eW[i][j] + " - " + What[i][j] + " = " + derivative[index - 1]); } } } if (index != beforeOutputWeights) throw new RuntimeException("after W derivative, index("+index+") != beforeOutputWeights("+beforeOutputWeights+")"); if (useOutputLayer) { for (int i = 0; i < eU4Edge.length; i++) { for (int j = 0; j < eU4Edge[i].length; j++) { derivative[index++] = (eU4Edge[i][j] - Uhat4Edge[i][j]); if (VERBOSE) { log.info("outputLayerWeights4Edge deriv(" + i + "," + j + ") = " + eU4Edge[i][j] + " - " + Uhat4Edge[i][j] + " = " + derivative[index - 1]); } } } for (int i = 0; i < eU.length; i++) { for (int j = 0; j < eU[i].length; j++) { derivative[index++] = (eU[i][j] - Uhat[i][j]); if (VERBOSE) { log.info("outputLayerWeights deriv(" + i + "," + j + ") = " + eU[i][j] + " - " + Uhat[i][j] + " = " + derivative[index - 1]); } } } } if (index != x.length) throw new RuntimeException("after W derivative, index("+index+") != x.length("+x.length+")"); int regSize = x.length; if (flags.skipOutputRegularization || flags.softmaxOutputLayer) { regSize = beforeOutputWeights; } // incorporate priors if (prior == QUADRATIC_PRIOR) { double sigmaSq = sigma * sigma; for (int i = 0; i < regSize; i++) { double k = 1.0; double w = x[i]; value += k * w * w / 2.0 / sigmaSq; derivative[i] += k * w / sigmaSq; } } else if (prior == HUBER_PRIOR) { double sigmaSq = sigma * sigma; for (int i = 0; i < regSize; i++) { double w = x[i]; double wabs = Math.abs(w); if (wabs < epsilon) { value += w * w / 2.0 / epsilon / sigmaSq; derivative[i] += w / epsilon / sigmaSq; } else { value += (wabs - epsilon / 2) / sigmaSq; derivative[i] += ((w < 0.0) ? -1.0 : 1.0) / sigmaSq; } } } else if (prior == QUARTIC_PRIOR) { double sigmaQu = sigma * sigma * sigma * sigma; for (int i = 0; i < regSize; i++) { double k = 1.0; double w = x[i]; value += k * w * w * w * w / 2.0 / sigmaQu; derivative[i] += k * w / sigmaQu; } } } public double[][] emptyFull2D() { double[][] d = new double[map.length][]; // int index = 0; for (int i = 0; i < map.length; i++) { d[i] = new double[labelIndices.get(map[i]).size()]; // cdm july 2005: below array initialization isn't necessary: JLS (3rd ed.) 4.12.5 // Arrays.fill(d[i], 0.0); // index += labelIndices.get(map[i]).size(); } return d; } }