Example usage for java.lang Math sqrt

Introduction

In this page you can find the example usage for java.lang Math sqrt.

Prototype

@HotSpotIntrinsicCandidate
public static double sqrt(double a)

Source Link

Document

Returns the correctly rounded positive square root of a double value.

Usage

From source file:Main.java

public static double getAcceleration(SensorEvent event) {
    final float x = event.values[0];
    final float y = event.values[1];
    final float z = event.values[2];
    double sqrt = Math.sqrt(Math.abs(x * x) + Math.abs(y * y) + Math.abs(z * z));
    return sqrt;/*  w  w  w.j  a v a  2s  .co  m*/
}

From source file:Main.java

public static double calScaleRatio(int originalWidth, int originalHeight, int targetWidth, int targetHeight) {
    if (originalWidth == 0 || originalHeight == 0) {
        return 1;
    } else {// w  w  w  .  j  av  a2s . c om
        double ratio = Math.sqrt((targetWidth * targetHeight * 1.0) / (originalWidth * originalHeight));
        if (ratio > 1) {
            return 1;
        } else {
            return ratio;
        }
    }
}

From source file:Main.java

public static double colorDistanceCore(double[] lab1, double[] lab2) {
    double[] lab = new double[] { lab2[0] - lab1[0], lab2[1] - lab1[1], lab2[2] - lab1[2] };
    double C1 = Math.sqrt(lab1[1] * lab1[1] + lab1[2] * lab1[2]);
    double C2 = Math.sqrt(lab2[1] * lab2[1] + lab2[2] * lab2[2]);
    double Ci = C2 - C1;
    double Hi = Math.sqrt(Math.max(lab[1] * lab[1] + lab[2] * lab[2] - Ci * Ci, 0));

    double kL = 1, kC = 1, kH = 1, K1 = .045, K2 = .015;
    double SL = 1, SC = 1 + K1 * C2, SH = 1 + K2 * C2;
    double dL = lab[0] / (kL * SL), dC = Ci / (kC * SC), dH = Hi / (kH * SH);
    return Math.sqrt(dL * dL + dC * dC + dH * dH);
}

From source file:Main.java

public static double getStrength(String[] word) {
    double result = 0.0;
    for (int i = 0; i < word.length; i++) {
        result = result + (Double.parseDouble(word[i])) * (Double.parseDouble(word[i]));
    }//from w w w.j  a  v  a  2  s.  c om
    return Math.sqrt(result);
}

From source file:Main.java

public static double tile2lat(int y, int aZoom) {

    final double MerkElipsK = 0.0000001;
    final long sradiusa = 6378137;
    final long sradiusb = 6356752;
    final double FExct = (double) Math.sqrt(sradiusa * sradiusa - sradiusb * sradiusb) / sradiusa;
    final int TilesAtZoom = 1 << aZoom;
    double result = (y - TilesAtZoom / 2) / -(TilesAtZoom / (2 * Math.PI));
    result = (2 * Math.atan(Math.exp(result)) - Math.PI / 2) * 180 / Math.PI;
    double Zu = result / (180 / Math.PI);
    double yy = ((y) - TilesAtZoom / 2);

    double Zum1 = Zu;
    Zu = Math.asin(1 - ((1 + Math.sin(Zum1)) * Math.pow(1 - FExct * Math.sin(Zum1), FExct))
            / (Math.exp((2 * yy) / -(TilesAtZoom / (2 * Math.PI)))
                    * Math.pow(1 + FExct * Math.sin(Zum1), FExct)));
    while (Math.abs(Zum1 - Zu) >= MerkElipsK) {
        Zum1 = Zu;/* www .j  a  va2 s.c o m*/
        Zu = Math.asin(1 - ((1 + Math.sin(Zum1)) * Math.pow(1 - FExct * Math.sin(Zum1), FExct))
                / (Math.exp((2 * yy) / -(TilesAtZoom / (2 * Math.PI)))
                        * Math.pow(1 + FExct * Math.sin(Zum1), FExct)));
    }

    result = Zu * 180 / Math.PI;

    return result;

}

From source file:Main.java

public static double calDistance(double latX, double lngX, double latY, double lngY) {
    double scale = 6400 * 1000 * (Math.PI / 180);
    double dX = scale * Math.abs((latX - latY));
    double dY = scale * Math.abs((lngX - lngY));
    return Math.sqrt(dX * dX + dY * dY);
}

From source file:Main.java

public static long compute(long timeInNanosecond) {
    final long start = System.nanoTime();
    long seed = start;
    while (System.nanoTime() - start < timeInNanosecond) {
        seed = (long) Math.sqrt(3.15);
    }/*from   w ww .  j av a2 s.  c o  m*/
    return seed;

    //            try {
    //                TimeUnit.NANOSECONDS.sleep(timeInNanosecond);
    //            } catch (InterruptedException e) {
    //                e.printStackTrace();
    //            }
    //                return 0;
}

From source file:Main.java

public static boolean[] is_prime_up_to_with_sieve(int num) {
    boolean[] prime = new boolean[num + 1];
    Arrays.fill(prime, true);/*from w  w w  .j  a  v a2  s . co  m*/
    prime[0] = false;
    prime[1] = false;
    int num_sqrt = (int) Math.ceil(Math.sqrt(num));

    for (int i = 2; i <= num_sqrt; i++) {
        if (prime[i])
            for (int j = i * i; j <= num; j += i)
                prime[j] = false;
    }
    return prime;
}

From source file:Main.java

public static boolean isTablet(Activity activity) {
    DisplayMetrics dm = new DisplayMetrics();
    activity.getWindowManager().getDefaultDisplay().getMetrics(dm);
    double diagonalPixels = Math.sqrt(Math.pow(dm.widthPixels, 2) + Math.pow(dm.heightPixels, 2));
    double physicalSize = diagonalPixels / (160 * dm.density);
    return physicalSize > 7;
}

From source file:Main.java

public static float getCurrentScaleFromMatrix(Matrix matrix) {
    float[] values = new float[9];
    matrix.getValues(values);//from   ww  w . jav a  2 s.  c  om
    float scalex = values[Matrix.MSCALE_X];
    float skewy = values[Matrix.MSKEW_Y];
    return (float) Math.sqrt(scalex * scalex + skewy * skewy);
}