public double exactSolution(double asset, double time) { setup(asset, time); return -asset * Math.exp(-dividend * (maturityTime - time)) * SpecialFunctions.normalCdf(-d[0]) + strike * Math.exp(-interestRate * (maturityTime - time)) * SpecialFunctions.normalCdf(-d[1]); }
private double modelLevyAsian(double S, double K, double r, double div, double sig, double T) { double valueLevy = 0.0; double se = 0.0; double m = 0.0; double d = 0.0; double sv = 0.0; double xStar = 0.0; double d1, d2 = 0.0; double b = r - div; // cost of carry rate double t2 = T; // remaining time to maturity double sa = S; // Arithmetic Average price se = S / (T * b) * (Math.exp((b - r) * t2) - Math.exp(-r * t2)); m = 2 * Math.pow(S, 2) / (b + Math.pow(sig, 2)) * ((Math.exp((2 * b + Math.pow(sig, 2)) * t2) - 1) / (2 * b + Math.pow(sig, 2)) - (Math.exp(b * t2) - 1) / b); d = m / Math.pow(T, 2); sv = Math.log(d) - 2 * (r * t2 + Math.log(se)); xStar = K - ((T - t2) / T) * sa; d1 = 1 / Math.sqrt(sv) * (Math.log(d) / 2 - Math.log(xStar)); d2 = d1 - Math.sqrt(sv); valueLevy = se * CND(d1) - xStar * Math.exp(-r * t2) * CND(d2); return valueLevy; }
// loss = add( w[i] * log(1+exp(-y[i]* weightT * x[i])) ) + 0.5 * lbfgs_l2_c * ||weight||2 @Override public void map(AvroKey<lbfgsdata> key, NullWritable nullvalue, Context context) { lbfgsdata data = key.datum(); float w = data.getWeight(); float offset = data.getOffset(); int y = data.getResponse(); List<entry> l = data.getFeatures(); double decision_value = 0.0; for (entry e : l) { decision_value += e.getValue() * weight[e.getIndex()]; } decision_value += offset; double loss_temp; loss_temp = y * decision_value; if (loss_temp > 0) { loss_temp = Math.log(1 + Math.exp(-loss_temp)); } else { loss_temp = ((-loss_temp) + Math.log(1 + Math.exp(loss_temp))); } loss += w * loss_temp; double gradient_temp = (1 / (1 + Math.exp(-y * decision_value)) - 1) * y * w; for (entry e : l) { gradient[e.getIndex()] += gradient_temp * e.getValue(); } }
/** * Compute theta price of cash-or-nothing option * * @param spot The spot * @param strike The strike * @param timeToExpiry The time to expiry * @param lognormalVol The log-normal volatility * @param interestRate The interest rate * @param costOfCarry The cost-of-carry * @param isCall True for calls, false for puts * @return The option price */ public static double theta( final double spot, final double strike, final double timeToExpiry, final double lognormalVol, final double interestRate, final double costOfCarry, final boolean isCall) { ArgumentChecker.isTrue(spot > 0.0, "negative/NaN spot; have {}", spot); ArgumentChecker.isTrue(strike > 0.0, "negative/NaN strike; have {}", strike); ArgumentChecker.isTrue(timeToExpiry > 0.0, "negative/NaN timeToExpiry; have {}", timeToExpiry); ArgumentChecker.isTrue(lognormalVol > 0.0, "negative/NaN lognormalVol; have {}", lognormalVol); ArgumentChecker.isFalse(Double.isNaN(interestRate), "interestRate is NaN"); ArgumentChecker.isFalse(Double.isNaN(costOfCarry), "costOfCarry is NaN"); final double d = (Math.log(spot / strike) + (costOfCarry - 0.5 * lognormalVol * lognormalVol) * timeToExpiry) / lognormalVol / Math.sqrt(timeToExpiry); final double sign = isCall ? 1. : -1.; final double div = 0.5 * (-Math.log(spot / strike) / Math.pow(timeToExpiry, 1.5) + (costOfCarry - 0.5 * lognormalVol * lognormalVol) / Math.pow(timeToExpiry, 0.5)) / lognormalVol; return interestRate * Math.exp(-interestRate * timeToExpiry) * NORMAL.getCDF(sign * d) - sign * Math.exp(-interestRate * timeToExpiry) * NORMAL.getPDF(d) * div; }
private void getnegphase() { /* * It does the negative phase of unsupervised RBM training algorithm * * For details, please refer to Dr. Hinton's paper: * Reducing the dimensionality of data with neural networks. Science, Vol. 313. no. 5786, pp. 504 - 507, 28 July 2006. */ // start calculate the negative phase // calculate the curved value of v1,h1 // find the vector of v1 Matrix negdata = poshidstates.times(vishid.transpose()); // (1 * numhid) * (numhid * numdims) = (1 * numdims) negdata.plusEquals(visbiases); // poshidstates*vishid' + visbiases double[][] tmp1 = negdata.getArray(); int i1 = 0; while (i1 < numdims) { tmp1[0][i1] = 1 / (1 + Math.exp(-tmp1[0][i1])); i1++; } // find the vector of h1 neghidprobs = negdata.times(vishid); // (1 * numdims) * (numdims * numhid) = (1 * numhid) neghidprobs.plusEquals(hidbiases); double[][] tmp2 = neghidprobs.getArray(); int i2 = 0; while (i2 < numhid) { tmp2[0][i2] = 1 / (1 + Math.exp(-tmp2[0][i2])); i2++; } negprods = negdata.transpose().times(neghidprobs); // (numdims * 1) *(1 * numhid) = (numdims * numhid) }
public Double eval(Double gamma) { double c = 1.0 / (double) Math.sqrt(variance); double sum = 0.0; for (Integer i : transcripts.get(gammat)) { double pi = 0.0; for (int t = 0; t < fiveprime.length; t++) { if (transcripts.get(t).contains(i)) { double gammai = gammat == t ? gamma : gammas[t][gammak]; double dit = delta(i, t); double pit = gammai * Math.exp(-lambda * dit); pi += pit; } } double zi = Math.log(pi); double err = data.values(i)[channels[gammak]] - zi; double ratio = (Math.exp(-lambda * delta(i, gammat))) / pi; double termi = (err * ratio); sum += termi; } return c * sum; }
public final double lgrad(double u, double a, Loss loss) { assert loss.isForNumeric() : "Loss function " + loss + " not applicable to numerics"; switch (loss) { case Quadratic: return 2 * (u - a); case Absolute: return Math.signum(u - a); case Huber: return Math.abs(u - a) <= 1 ? u - a : Math.signum(u - a); case Poisson: assert a >= 0 : "Poisson loss L(u,a) requires variable a >= 0"; return Math.exp(u) - a; case Hinge: // return a*u <= 1 ? -a : 0; return a == 0 ? (-u <= 1 ? 1 : 0) : (u <= 1 ? -1 : 0); // Booleans are coded as {0,1} instead of {-1,1} case Logistic: // return -a/(1+Math.exp(a*u)); return a == 0 ? 1 / (1 + Math.exp(-u)) : -1 / (1 + Math.exp(u)); // Booleans are coded as {0,1} instead of {-1,1} case Periodic: return ((2 * Math.PI) / _period) * Math.sin((a - u) * (2 * Math.PI) / _period); default: throw new RuntimeException("Unknown loss function " + loss); } }
public void forwardIBD() { int numNodes = treeModel.getNodeCount(); int stateCount = substitutionModel.getStateCount(); getDiagonalRates(diag); for (int nodeId = 0; nodeId < numNodes; ++nodeId) { NodeRef node = treeModel.getNode(nodeId); NodeRef parent = treeModel.getParent(node); if (parent == null) { // handle the root } else if (treeModel.isExternal(node)) { // Handle the tip double branchTime = branchRateModel.getBranchRate(treeModel, node) * (treeModel.getNodeHeight(parent) - treeModel.getNodeHeight(node)); for (int state = 0; state < stateCount; ++state) { ibdForward[nodeId][state] = Math.exp(-diag[state] * branchTime); } } else { // Handle internal node double branchTime = branchRateModel.getBranchRate(treeModel, node) * (treeModel.getNodeHeight(parent) - treeModel.getNodeHeight(node)); int childCount = treeModel.getChildCount(node); for (int state = 0; state < stateCount; ++state) { ibdForward[nodeId][state] = 0; for (int child = 0; child < childCount; ++child) { int childNodeId = treeModel.getChild(node, child).getNumber(); ibdForward[nodeId][state] += ibdForward[childNodeId][state]; } ibdForward[nodeId][state] *= Math.exp(-diag[state] * branchTime); } } } }
public final double loss(double u, double a, Loss loss) { assert loss.isForNumeric() : "Loss function " + loss + " not applicable to numerics"; switch (loss) { case Quadratic: return (u - a) * (u - a); case Absolute: return Math.abs(u - a); case Huber: return Math.abs(u - a) <= 1 ? 0.5 * (u - a) * (u - a) : Math.abs(u - a) - 0.5; case Poisson: assert a >= 0 : "Poisson loss L(u,a) requires variable a >= 0"; return Math.exp(u) + (a == 0 ? 0 : -a * u + a * Math.log(a) - a); // Since \lim_{a->0} a*log(a) = 0 case Hinge: // return Math.max(1-a*u,0); return Math.max(1 - (a == 0 ? -u : u), 0); // Booleans are coded {0,1} instead of {-1,1} case Logistic: // return Math.log(1 + Math.exp(-a * u)); return Math.log( 1 + Math.exp(a == 0 ? u : -u)); // Booleans are coded {0,1} instead of {-1,1} case Periodic: return 1 - Math.cos((a - u) * (2 * Math.PI) / _period); default: throw new RuntimeException("Unknown loss function " + loss); } }
public void printChildTopWords(int k, String childBetaFile) { try { System.out.println("child beta file"); PrintWriter childBetaOut = new PrintWriter(new File(childBetaFile)); for (int i = 0; i < m_childTopicTermProb.length; i++) { MyPriorityQueue<_RankItem> fVector = new MyPriorityQueue<_RankItem>(k); for (int j = 0; j < vocabulary_size; j++) fVector.add(new _RankItem(m_corpus.getFeature(j), m_childTopicTermProb[i][j])); childBetaOut.format("Topic %d(%.3f):\t", i, m_childSstat[i]); System.out.format("Topic %d(%.3f):\t", i, m_childSstat[i]); for (_RankItem it : fVector) { childBetaOut.format( "%s(%.3f)\t", it.m_name, m_logSpace ? Math.exp(it.m_value) : it.m_value); System.out.format( "%s(%.3f)\t", it.m_name, m_logSpace ? Math.exp(it.m_value) : it.m_value); } childBetaOut.println(); System.out.println(); } childBetaOut.flush(); childBetaOut.close(); } catch (Exception ex) { System.err.print("File Not Found"); } }
public void printTopWords(int k, String betaFile) { Arrays.fill(m_parentSstat, 0); Arrays.fill(m_childSstat, 0); System.out.println("print top words"); for (_Doc d : m_trainSet) { if (d instanceof _ParentDoc2) { // print out topic assignment of parent printParentTopicAssignment((_ParentDoc2) d); for (int i = 0; i < number_of_topics; i++) m_parentSstat[i] += m_logSpace ? Math.exp(d.m_topics[i]) : d.m_topics[i]; } else if (d instanceof _ChildDoc2) { // print out topic assignment of child printChildTopicAssignment((_ChildDoc2) d); for (int i = 0; i < number_of_topics; i++) m_childSstat[i] += m_logSpace ? Math.exp(d.m_topics[i]) : d.m_topics[i]; } } Utils.L1Normalization(m_parentSstat); Utils.L1Normalization(m_childSstat); String parentBetaFile = betaFile.replace(".txt", "parent.txt"); String childBetaFile = betaFile.replace(".txt", "child.txt"); printParentTopWords(k, parentBetaFile); printChildTopWords(k, childBetaFile); String parentParameterFile = parentBetaFile.replace("beta", "parameter"); String childParameterFile = childBetaFile.replace("beta", "parameter"); printParameter(parentParameterFile, childParameterFile); }
@Override public PerformanceVector evaluateIndividual(Individual individual) { double[] beta = individual.getValues(); double fitness = 0.0d; for (Example example : exampleSet) { double eta = 0.0d; int i = 0; for (Attribute attribute : example.getAttributes()) { double value = example.getValue(attribute); eta += beta[i] * value; i++; } if (addIntercept) { eta += beta[beta.length - 1]; } double pi = Math.exp(eta) / (1 + Math.exp(eta)); double classValue = example.getValue(label); double currentFitness = classValue * Math.log(pi) + (1 - classValue) * Math.log(1 - pi); double weightValue = 1.0d; if (weight != null) weightValue = example.getValue(weight); fitness += weightValue * currentFitness; } PerformanceVector performanceVector = new PerformanceVector(); performanceVector.addCriterion( new EstimatedPerformance("log_reg_fitness", fitness, exampleSet.size(), false)); return performanceVector; }
private static List<Queue<Pair<String, Double>>> topWordsForTopics( String dir, Configuration job, List<String> wordList, int numWordsToPrint) { List<Queue<Pair<String, Double>>> queues = Lists.newArrayList(); Map<Integer, Double> expSums = Maps.newHashMap(); for (Pair<IntPairWritable, DoubleWritable> record : new SequenceFileDirIterable<IntPairWritable, DoubleWritable>( new Path(dir, "part-*"), PathType.GLOB, null, null, true, job)) { IntPairWritable key = record.getFirst(); int topic = key.getFirst(); int word = key.getSecond(); ensureQueueSize(queues, topic); if (word >= 0 && topic >= 0) { double score = record.getSecond().get(); if (expSums.get(topic) == null) { expSums.put(topic, 0.0); } expSums.put(topic, expSums.get(topic) + Math.exp(score)); String realWord = wordList.get(word); maybeEnqueue(queues.get(topic), realWord, score, numWordsToPrint); } } for (int i = 0; i < queues.size(); i++) { Queue<Pair<String, Double>> queue = queues.get(i); Queue<Pair<String, Double>> newQueue = new PriorityQueue<Pair<String, Double>>(queue.size()); double norm = expSums.get(i); for (Pair<String, Double> pair : queue) { newQueue.add(new Pair<String, Double>(pair.getFirst(), Math.exp(pair.getSecond()) / norm)); } queues.set(i, newQueue); } return queues; }
public Complex tanh() { double scalar; double temp1Re, temp1Im; double temp2Re, temp2Im; Complex sinRes, cosRes; // tanh(z) = sinh(z) / cosh(z) scalar = Math.exp(re); temp1Re = scalar * Math.cos(im); temp1Im = scalar * Math.sin(im); scalar = Math.exp(-re); temp2Re = scalar * Math.cos(-im); temp2Im = scalar * Math.sin(-im); temp1Re -= temp2Re; temp1Im -= temp2Im; sinRes = new Complex(0.5 * temp1Re, 0.5 * temp1Im); scalar = Math.exp(re); temp1Re = scalar * Math.cos(im); temp1Im = scalar * Math.sin(im); scalar = Math.exp(-re); temp2Re = scalar * Math.cos(-im); temp2Im = scalar * Math.sin(-im); temp1Re += temp2Re; temp1Im += temp2Im; cosRes = new Complex(0.5 * temp1Re, 0.5 * temp1Im); return sinRes.div(cosRes); }
private void validateMedian(double rake, double[][] table) { String[] columnDescr = TABLE_HEADER_MEDIAN[0].trim().split("\\s+"); // check for SA for (int i = 3; i < columnDescr.length - 1; i++) { for (int j = 0; j < table.length; j++) { int iper = i - 2; double mag = table[j][0]; double rJB = table[j][1]; double expectedMedian = table[j][i]; double computedMedian = Math.exp(toro2002SHARE.getMean(iper, mag, rJB, rake)); computedMedian = computedMedian / (AdjustFactorsSHARE.AFrock_TORO2002[iper] * toro2002SHARE.computeStyleOfFaultingTerm(iper, rake)[2]); assertEquals(expectedMedian, computedMedian, TOLERANCE); } } // check for PGA for (int j = 0; j < table.length; j++) { double mag = table[j][0]; double rJB = table[j][1]; double expectedMedian = table[j][columnDescr.length - 1]; double computedMedian = Math.exp(toro2002SHARE.getMean(0, mag, rJB, rake)); computedMedian = computedMedian / (AdjustFactorsSHARE.AFrock_TORO2002[0] * toro2002SHARE.computeStyleOfFaultingTerm(0, rake)[2]); assertEquals(expectedMedian, computedMedian, TOLERANCE); } }
/** Returns the sine of this complex number. */ public Complex sin() { double izRe, izIm; double temp1Re, temp1Im; double temp2Re, temp2Im; double scalar; // sin(z) = ( exp(i*z) - exp(-i*z) ) / (2*i) izRe = -im; izIm = re; // first exp scalar = Math.exp(izRe); temp1Re = scalar * Math.cos(izIm); temp1Im = scalar * Math.sin(izIm); // second exp scalar = Math.exp(-izRe); temp2Re = scalar * Math.cos(-izIm); temp2Im = scalar * Math.sin(-izIm); temp1Re -= temp2Re; temp1Im -= temp2Im; return new Complex(0.5 * temp1Im, -0.5 * temp1Re); }
/** Returns the cosine of this complex number. */ public Complex cos() { double izRe, izIm; double temp1Re, temp1Im; double temp2Re, temp2Im; double scalar; // cos(z) = ( exp(i*z) + exp(-i*z) ) / 2 izRe = -im; izIm = re; // first exp scalar = Math.exp(izRe); temp1Re = scalar * Math.cos(izIm); temp1Im = scalar * Math.sin(izIm); // second exp scalar = Math.exp(-izRe); temp2Re = scalar * Math.cos(-izIm); temp2Im = scalar * Math.sin(-izIm); temp1Re += temp2Re; temp1Im += temp2Im; return new Complex(0.5 * temp1Re, 0.5 * temp1Im); }
/** * Return the probability density for a particular point. * * @param x The point at which the density should be computed. * @return The pdf at point x. */ public double density(Double x) { if (x < 0) return 0; return Math.pow(x / getBeta(), getAlpha() - 1) / getBeta() * Math.exp(-x / getBeta()) / Math.exp(Gamma.logGamma(getAlpha())); }
private ArrayList<Double> forwardProp(Double[] input) { for (int i = 0; i < hiddenLNo; i++) { for (int j = 0; j < inputSize + 1; j++) { if (j == inputSize) { hiddenNodes.set(i, hiddenNodes.get(i) + w1[j][i] * bias); } else { hiddenNodes.set(i, hiddenNodes.get(i) + w1[j][i] * input[j]); } } double temp = (1.0 / (1.0 + Math.exp(-hiddenNodes.get(i)))); hiddenNodes.set(i, temp); } for (int i = 0; i < outputLNo; i++) { for (int j = 0; j < hiddenLNo + 1; j++) { if (j == hiddenNodes.size()) { outputNodes.set(i, outputNodes.get(i) + w2[j][i] * bias); } else { outputNodes.set(i, outputNodes.get(i) + w2[j][i] * hiddenNodes.get(j)); } } // double temp1 = (1.0 / (1.0 + Math.exp(-outputNodes.get(i)))); outputNodes.set(i, (1.0 / (1.0 + Math.exp(-outputNodes.get(i))))); } return outputNodes; }
@Test public void meanShift() { int w = 32; CirculantTracker<ImageFloat32> alg = new CirculantTracker<ImageFloat32>(1f / 16, 0.2, 1e-2, 0.075, 1.0, w, 255, interp); int peakX = 13; int peakY = 17; alg.getResponse().reshape(w, w); for (int i = 0; i < w; i++) { double b = Math.exp(-(i - peakY) * (i - peakY) / 3.0); for (int j = 0; j < w; j++) { double a = Math.exp(-(j - peakX) * (j - peakX) / 3.0); alg.getResponse().set(j, i, a * b); } } alg.subpixelPeak(peakX - 2, peakY + 1); assertEquals(2, alg.offX, 0.3); assertEquals(-1, alg.offY, 0.3); }
public double protectionLeg(IsdaCompliantCreditCurve creditCurve) { double ht0 = creditCurve.getRT(_proLegIntPoints[0]); double rt0 = _proYieldCurveRT[0]; double b0 = _proDF[0] * Math.exp(-ht0); double pv = 0.0; for (int i = 1; i < _nProPoints; ++i) { double ht1 = creditCurve.getRT(_proLegIntPoints[i]); double rt1 = _proYieldCurveRT[i]; double b1 = _proDF[i] * Math.exp(-ht1); double dht = ht1 - ht0; double drt = rt1 - rt0; double dhrt = dht + drt; // this is equivalent to the ISDA code without explicitly calculating the time step - it // also handles the limit double dPV; if (Math.abs(dhrt) < 1e-5) { dPV = dht * b0 * epsilon(-dhrt); } else { dPV = (b0 - b1) * dht / dhrt; } pv += dPV; ht0 = ht1; rt0 = rt1; b0 = b1; } pv *= _lgdDF; // multiply by LGD and adjust to valuation date return pv; }
/** * Perform the mutation strength strategy vector mutation for Evolution Strategies (Chapter 30) as * specified in Algorithm 30.8. * * @param g the existing genotype in the search space from which a slightly modified copy should * be created * @param r the random number generator * @return a new genotype */ @Override public final double[] mutate(final double[] g, final Random r) { final double[] gnew; final double t0, t, c, nu; int i; double x; i = g.length; c = 1d; // set tau0 according to Equation 30.12 t0 = (c / Math.sqrt(2 * i)); // set tau according to Equation 30.13 t = (c / Math.sqrt(2 * Math.sqrt(i))); nu = Math.exp(t0 * r.nextGaussian()); gnew = g.clone(); // set each gene Definition D4.3 of gnew to ... for (; (--i) >= 0; ) { do { x = gnew[i] * nu * Math.exp(t * r.nextGaussian()); } while ((x < this.min) || (x > this.max)); gnew[i] = x; } return gnew; }
public synchronized double nextGamma(double alpha, double beta) { double gamma = 0; if (alpha <= 0 || beta <= 0) { throw new IllegalArgumentException("alpha and beta must be strictly positive."); } if (alpha < 1) { double b, p; boolean flag = false; b = 1 + alpha * Math.exp(-1); while (!flag) { p = b * random.nextDouble(); if (p > 1) { gamma = -Math.log((b - p) / alpha); if (random.nextDouble() <= Math.pow(gamma, alpha - 1)) flag = true; } else { gamma = Math.pow(p, 1 / alpha); if (random.nextDouble() <= Math.exp(-gamma)) flag = true; } } } else if (alpha == 1) { gamma = -Math.log(random.nextDouble()); } else { double y = -Math.log(random.nextDouble()); while (random.nextDouble() > Math.pow(y * Math.exp(1 - y), alpha - 1)) y = -Math.log(random.nextDouble()); gamma = alpha * y; } return beta * gamma; }
/** * Calculate fine fuel moisture: moisture of litter measured in %. * * @param dryBulbTemperature * @param wetBulbTemperature * @param herbstate * @return double */ private double calculateFineFuelMoisture( double dryBulbTemperature, double wetBulbTemperature, HerbState herbstate) { double deltaT = dryBulbTemperature - wetBulbTemperature; double ffm = 0.; // fine fuel moisture if (deltaT <= diffTemperature[0]) { ffm = constantsFineFuelMoisture[0][0] * Math.exp(constantsFineFuelMoisture[1][0] * deltaT); } else if (deltaT <= diffTemperature[1]) { ffm = constantsFineFuelMoisture[0][1] * Math.exp(constantsFineFuelMoisture[1][1] * deltaT); } else if (deltaT <= diffTemperature[2]) { ffm = constantsFineFuelMoisture[0][2] * Math.exp(constantsFineFuelMoisture[1][2] * deltaT); } else { ffm = constantsFineFuelMoisture[0][3] * Math.exp(constantsFineFuelMoisture[1][3] * deltaT); } /** if ffm is smaller than one, set it to one */ if (ffm < 1.) { ffm = 1.; } /** adjust fine fuel moisture according to herb state */ if (herbstate == HerbState.TRANSITION) { ffm = ffm + 5.; } else if (herbstate == HerbState.GREEN) { ffm = ffm + 10.; } return ffm; }
public String classifyWhole(File file) { double[] probabilities = new double[genres.length]; // array of initial probabilities. int current = 0; // array counter. for (MarkovModel mm : mms) // for every MarkovModel in the array. { probabilities[current] = mm.probabilityWhole(file); // get initial probability from the Markov Model. ++current; } double[] realProbabilities = new double[genres.length]; // Array of calculated probabilities. int max = 0; // Pointer to maximum probability. for (int i = 0; i < genres.length; ++i) // Calculate probability for each genre. { double sum = 0; for (int j = 0; j < genres.length; ++j) // Sum of the probabilities in different genres. { sum += Math.exp(probabilities[j]); } realProbabilities[i] = Math.exp(probabilities[i]) / sum; // Calculating final probability. if (realProbabilities[i] > realProbabilities[max]) // recalculating max probability. { max = i; } } for (int i = 0; i < genres.length; ++i) { System.out.println(genres[i] + " : " + probabilities[i]); } return genres[max]; // returning corresponding genre. }
/** * Creates an undirected model that corresponds to a Boltzmann machine with the given weights and * biases. * * @param weights * @param biases * @return An appropriate UndirectedModel. */ public static UndirectedModel createBoltzmannMachine(double[][] weights, double[] biases) { if (weights.length != biases.length) throw new IllegalArgumentException( "Number of weights " + weights.length + " not equal to number of biases " + biases.length); int numV = weights.length; Variable vars[] = new Variable[numV]; for (int i = 0; i < numV; i++) vars[i] = new Variable(2); UndirectedModel mdl = new UndirectedModel(vars); for (int i = 0; i < numV; i++) { Factor nodePtl = new TableFactor(vars[i], new double[] {1, Math.exp(biases[i])}); mdl.addFactor(nodePtl); for (int j = i + 1; j < numV; j++) { if (weights[i][j] != 0) { double[] ptl = new double[] {1, 1, 1, Math.exp(weights[i][j])}; mdl.addFactor(vars[i], vars[j], ptl); } } } return mdl; }
private double modelTurnbullWakemanAsian( double S, double K, double r, double div, double sig, double T) { // constant double b = r - div; // cost of carry rate double tau = 0.0; // time to the begining of the average period double m1 = 0.0; double m2 = 0.0; double optionValue = 0.0; double x = 0.0; m1 = ((Math.exp(b * T) - Math.exp(b * tau)) / (b * (T - tau))) * S; m2 = Math.pow(S, 2) * 2 * Math.exp((2 * b + Math.pow(sig, 2)) * T) / ((b + Math.pow(sig, 2)) * (2 * b + Math.pow(sig, 2)) * Math.pow(T - tau, 2)) + (Math.pow(S, 2) * 2 * Math.exp((2 * b + Math.pow(sig, 2)) * tau) / (b * Math.pow(T - tau, 2))) * (1 / (2 * b + Math.pow(sig, 2)) - (Math.exp(b * (T - tau))) / (b + Math.pow(sig, 2))); System.out.println("M:" + m2); double modVol = Math.sqrt((1 / T) * Math.log(m2 / Math.pow(m1, 2))) * 100; optionValue = modelBlack76(K, m1, modVol, T, r); return optionValue; }
public static double[] getExpData(double[] axis, double scale) { double fraction = Math.exp(-axis[0]); double[] buffer = new double[axis.length]; for (int loop = 0; loop < axis.length; loop++) { buffer[loop] = scale * Math.exp(-axis[loop]) / fraction; } return buffer; }
/** * Computes x + y without losing precision using ln(x) and ln(y). * * @param lna Value. * @param lnc Value. * @return Result. */ public static double LogSum(float lna, float lnc) { if (lna == Float.NEGATIVE_INFINITY) return lnc; if (lnc == Float.NEGATIVE_INFINITY) return lna; if (lna > lnc) return lna + Special.Log1p(Math.exp(lnc - lna)); return lnc + Special.Log1p(Math.exp(lna - lnc)); }
private void process(int op, double value) { float c, v1, v2; boolean resetMinMax = roiWidth == width && roiHeight == height && !(op == FILL); c = (float) value; for (int y = roiY; y < (roiY + roiHeight); y++) { int i = y * width + roiX; for (int x = roiX; x < (roiX + roiWidth); x++) { v1 = pixels[i]; switch (op) { case INVERT: v2 = max - (v1 - min); break; case FILL: v2 = fillColor; break; case ADD: v2 = v1 + c; break; case MULT: v2 = v1 * c; break; case GAMMA: if (v1 <= 0f) v2 = 0f; else v2 = (float) Math.exp(c * Math.log(v1)); break; case LOG: if (v1 <= 0f) v2 = 0f; else v2 = (float) Math.log(v1); break; case EXP: v2 = (float) Math.exp(v1); break; case SQR: v2 = v1 * v1; break; case SQRT: if (v1 <= 0f) v2 = 0f; else v2 = (float) Math.sqrt(v1); break; case ABS: v2 = (float) Math.abs(v1); break; case MINIMUM: if (v1 < value) v2 = (float) value; else v2 = v1; break; case MAXIMUM: if (v1 > value) v2 = (float) value; else v2 = v1; break; default: v2 = v1; } pixels[i++] = v2; } } if (resetMinMax) findMinAndMax(); }