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

/**
 * Rotate a set of coordinates by a given angle
 * @param c_x/* w ww . j av a 2 s.  c  o  m*/
 * @param c_y
 * @param thetab
 * @param x
 * @param y
 * @return
 */
public static double[] rotateCoord(double c_x, double c_y, double thetab, double x, double y) {
    double prc_x = x - c_x;
    double prc_y = y - c_y;
    double r = Math.sqrt(prc_x * prc_x + prc_y * prc_y);
    double theta = Math.atan2(prc_y, prc_x);
    theta = theta + thetab * Math.PI / 180.0;
    double pc_x = r * Math.cos(theta);
    double pc_y = r * Math.sin(theta);
    double p[] = new double[2];
    p[0] = pc_x + c_x;
    p[1] = pc_y + c_y;
    return p;
}

From source file:Main.java

public static double getDistance(double longitude1, double latitude1, double longitude2, double latitude2) {

    double Lat1 = rad(latitude1);
    double Lat2 = rad(latitude2);
    double a = Lat1 - Lat2;
    double b = rad(longitude1) - rad(longitude2);
    double s = 2 * Math.asin(Math.sqrt(
            Math.pow(Math.sin(a / 2), 2) + Math.cos(Lat1) * Math.cos(Lat2) * Math.pow(Math.sin(b / 2), 2)));
    s = s * EARTH_RADIUS;/*from  ww  w .  j  av a 2 s .c  o m*/
    s = Math.round(s * 10000) / 10000;
    return s;
}

From source file:Main.java

public static List<String> calculateResolutions(double dpi, double screenSize, boolean standard) {
    List<String> ret = new ArrayList<>();
    double bothSquaredSum = Math.pow(dpi * screenSize, 2);
    for (int i = 0; i < 10000; i++) {
        double other = Math.sqrt(bothSquaredSum - Math.pow(i, 2));
        double higher = Math.max(i, other), lower = Math.min(i, other);
        if (Double.isNaN(lower)) {
            continue;
        }/*from   w w w  .  j a  v  a 2s  .c  o  m*/
        if (standard) {
            double ratio = higher / lower;
            if (ratio == 4.0 / 3.0 || ratio == 16.0 / 9.0 || ratio == 16.0 / 10.0) {
                ret.add(String.format("%.0fx%.0f", higher, lower));
            }
        } else {
            ret.add(String.format("%.0fx%.0f", higher, lower));
        }
    }
    return ret;
}

From source file:Main.java

public static double diffHsb(int hsb1[], final int hsb2[]) {
    if (hsb1 == null || hsb2 == null) {
        return 0.0;
    }/*from   www .  j  a  va2s.  c  o  m*/
    if (hsb1.length < 3 || hsb2.length < 3) {
        return 0.0;
    }

    double h = Math.pow(hsb1[0] - hsb2[0], 2);
    double s = Math.pow(hsb1[1] - hsb2[1], 2);
    double b = Math.pow(hsb1[2] - hsb2[2], 2);

    return Math.sqrt(h + s + b);
}

From source file:Main.java

/**
 * Get the vectors magnitude.//from ww w.  j a v a 2 s  .  co m
 *      v {1, 2, 3}
 *      |v| 3.74...
 *
 * @param v values of vector as arraylist.
 * @return magnitude
 */
public static double magnitudeVector(ArrayList<Double> v) {

    double vectorContent = 0;

    for (Double d : v) {
        vectorContent += Math.pow(d, 2);
    }

    return Math.sqrt(vectorContent);
}

From source file:Main.java

public static double gps2m(double lat_a, double lng_a, double lat_b, double lng_b) {
    double radLat1 = (lat_a * Math.PI / 180.0);
    double radLat2 = (lat_b * Math.PI / 180.0);
    double a = radLat1 - radLat2;
    double b = (lng_a - lng_b) * Math.PI / 180.0;
    double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2)
            + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));
    s = s * EARTH_RADIUS;// w  w  w.j a  v a  2s  . c  o  m
    s = Math.round(s * 10000) / 10000;
    return s;
}

From source file:Main.java

/**
 * Find the distance between two points.
 * //from  w w  w.ja  v a  2s  . c  om
 * @param one
 * @param two
 * @return the distance between point one and two
 */
private static float getDistanceBetweenTwoPoints(PointF one, PointF two) {
    float dx = one.x - two.x; // horizontal difference
    float dy = one.y - two.y; // vertical difference
    float dist = (float) Math.sqrt(dx * dx + dy * dy);

    return dist;
}

From source file:Main.java

public static float distanceBetween2Points(float vectorX0, float vectorY0, float vectorXP, float vectorYP) {
    float x = Math.abs(vectorXP - vectorX0);
    float y = Math.abs(vectorYP - vectorY0);
    return (float) Math.sqrt((x * x) + (y * y));
}

From source file:Main.java

public static void untransformBaidu(double wgLat, double wgLon, double[] latlng) {
    double x = wgLon - 0.0065, y = wgLat - 0.006;
    double z = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * x_pi);
    double theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * x_pi);
    double gg_lon = z * Math.cos(theta);
    double gg_lat = z * Math.sin(theta);
    untransform(gg_lat, gg_lon, latlng);
}

From source file:Main.java

private static int computeInitialSampleSize(BitmapFactory.Options options,

        int minSideLength, int maxNumOfPixels) {

    double w = options.outWidth;

    double h = options.outHeight;

    int lowerBound = (maxNumOfPixels == -1) ? 1 :

            (int) Math.ceil(Math.sqrt(w * h / maxNumOfPixels));

    int upperBound = (minSideLength == -1) ? 128 :

            (int) Math.min(Math.floor(w / minSideLength),

                    Math.floor(h / minSideLength));

    if (upperBound < lowerBound) {

        // return the larger one when there is no overlapping zone.

        return lowerBound;

    }/*  w w w .ja v a2  s . c  om*/

    if ((maxNumOfPixels == -1) &&

            (minSideLength == -1)) {

        return 1;

    } else if (minSideLength == -1) {

        return lowerBound;

    } else {

        return upperBound;

    }
}