List of usage examples for java.lang Math sqrt
@HotSpotIntrinsicCandidate public static double sqrt(double a)
From source file:hivemall.utils.math.StatsUtils.java
/** * probit(p)=sqrt(2)erf^-1(2p-1)/*ww w . j a va 2 s. c o m*/ * * <pre> * probit(1)=INF, probit(0)=-INF, probit(0.5)=0 * </pre> * * @param p must be in [0,1] * @link http://en.wikipedia.org/wiki/Probit */ public static double probit(double p) { if (p < 0 || p > 1) { throw new IllegalArgumentException("p must be in [0,1]"); } return Math.sqrt(2.d) * MathUtils.inverseErf(2.d * p - 1.d); }
From source file:com.opengamma.analytics.financial.timeseries.analysis.DifferenceSignIIDHypothesis.java
@Override public boolean testIID(final DoubleTimeSeries<?> x) { Validate.notNull(x, "x"); final double[] data = x.valuesArrayFast(); final int n = data.length; int t = 0;//from ww w.j av a2s .c o m for (int i = 1; i < n; i++) { if (data[i] > data[i - 1]) { t++; } } final double mean = (n - 1) / 2.; final double std = Math.sqrt((n + 1) / 12.); return Math.abs(t - mean) / std < _criticalValue; }
From source file:com.opengamma.analytics.math.function.special.OrthonormalHermitePolynomialFunction.java
@Override public DoubleFunction1D[] getPolynomials(final int n) { Validate.isTrue(n >= 0);/*w w w .jav a 2 s . c om*/ final DoubleFunction1D[] polynomials = new DoubleFunction1D[n + 1]; for (int i = 0; i <= n; i++) { if (i == 0) { polynomials[i] = F0; } else if (i == 1) { polynomials[i] = polynomials[0].multiply(Math.sqrt(2)).multiply(getX()); } else { polynomials[i] = polynomials[i - 1].multiply(getX()).multiply(Math.sqrt(2. / i)) .subtract(polynomials[i - 2].multiply(Math.sqrt((i - 1.) / i))); } } return polynomials; }
From source file:IK.G.java
public static double dist(double x1, double y1, double x2, double y2) { return Math.sqrt(Math.pow(x1 - x2, 2) + Math.pow(y1 - y2, 2)); }
From source file:es.udc.gii.common.eaf.util.EAFMath.java
public static double distance(List<Double> pI, List<Double> pJ) { double[] auxArray = new double[pI.size()]; for (int i = 0; i < pI.size(); i++) { auxArray[i] = pI.get(i) - pJ.get(i); }/*w ww. j a va2 s. c o m*/ double sumSq = StatUtils.sumSq(auxArray); return (sumSq == 0.0 ? 0.0 : Math.sqrt(sumSq)); }
From source file:Util.java
/** * Returns distance between two sets of coords * /*from w w w.j ava2s . c om*/ * @param x1 * first x coord * @param y1 * first y coord * @param x2 * second x coord * @param y2 * second y coord * @return distance between sets of coords */ public static double getDistance(float x1, float y1, float x2, float y2) { // using long to avoid possible overflows when multiplying double dx = x2 - x1; double dy = y2 - y1; // return Math.hypot(x2 - x1, y2 - y1); // Extremely slow // return Math.sqrt(Math.pow(x, 2) + Math.pow(y, 2)); // 20 times faster than hypot return Math.sqrt(dx * dx + dy * dy); // 10 times faster then previous line }
From source file:com.raghav.plot.XYSeriesDemo.java
/** * A demonstration application showing an XY series containing a null value. * * @param title the frame title.//from ww w . j a v a2 s . com */ public XYSeriesDemo(final String title) { super(title); final XYSeries series = new XYSeries("Random Data"); // float x=1; // float y=(float)((Math.sqrt(2))*x); // for (int i = 1; i < 200000; i++) { double x = (((double) (i)) / 1000); System.out.print("x = " + x); double xdb = 10 * (Math.log10(x)); System.out.print("\t 10logx=" + xdb); double y = Erf.erfc(Math.sqrt(x)); System.out.print("\t y=" + y); System.out.println("----------------------"); series.add(xdb, y); } final XYSeriesCollection data = new XYSeriesCollection(series); final JFreeChart chart = ChartFactory.createXYLineChart("XY Series Demo", "X", "Y", data, PlotOrientation.VERTICAL, true, true, false); final ChartPanel chartPanel = new ChartPanel(chart); chartPanel.setPreferredSize(new java.awt.Dimension(500, 270)); setContentPane(chartPanel); }
From source file:br.unicamp.ic.recod.gpsi.measures.gpsiHellingerDistanceScore.java
@Override public double score(double[][][] input) { double dist[][] = new double[2][]; int bins = 1000; dist[0] = MatrixUtils.createRealMatrix(input[0]).getColumn(0); dist[1] = MatrixUtils.createRealMatrix(input[1]).getColumn(0); gpsiHistogram hist = new gpsiHistogram(); double globalMin = (new Min()).evaluate(ArrayUtils.addAll(dist[0], dist[1])); double globalMax = (new Max()).evaluate(ArrayUtils.addAll(dist[0], dist[1])); double[] h0 = hist.distribution(dist[0], bins, globalMin, globalMax); double[] h1 = hist.distribution(dist[1], bins, globalMin, globalMax); double BC = 0.0; for (int i = 0; i < bins; i++) BC += Math.sqrt(h0[i] * h1[i]); return Math.sqrt(1 - BC); }
From source file:com.insightml.math.distributions.GaussianDistribution.java
public GaussianDistribution(final double mean, final double stddev) { this.mean = mean; this.stddev = stddev; sigmaSquare = stddev * stddev;/* w w w . j a v a2s . co m*/ factor = 1. / Math.sqrt(2 * Math.PI * sigmaSquare); }
From source file:com.opengamma.analytics.financial.model.option.pricing.tree.TimeVaryingLatticeSpecification.java
/** * Overloaded getParameters method /*from ww w .j ava 2 s . c o m*/ * @param vol Volatility * @param nu Computed by getShiftedDrift method * @param spaceStep Space step * @return {(modified time step), (up probability)} */ public double[] getParameters(final double vol, final double nu, final double spaceStep) { final double[] res = new double[2]; final double volSq = vol * vol; final double nuSq = nu * nu; res[0] = 0.5 * (-volSq + Math.sqrt(volSq * volSq + 4. * nuSq * spaceStep * spaceStep)) / nuSq; res[1] = 0.5 + 0.5 * nu * res[0] / spaceStep; return res; }