Knowledge Base Nr: 00333 tracking.java - http://www.swe-kaiser.de

Downloads:

Java: GWT: zurückgelegte strecke für tracking-daten

  
public static float GetTrackingLength(String sPoints)
{
    double fLen = 0;

    String pt[] = sPoints.split("#");
    if (pt.length < 2)
        return 0;

    String val[] = pt[0].split(" ");
    if (pt.length < 2)
        return 0;
    double fLastLat = Double.parseDouble(val[0]);
    double fLastLong = Double.parseDouble(val[1]);

    for (int n = 0; n < pt.length; n++)
    {
        String sCoord[] = pt[n].split(" ");

        double fLat = Double.parseDouble(sCoord[0]);
        double fLong = Double.parseDouble(sCoord[1]);

        //mit distance: Entfernung in km
        double lat1 = fLastLat;
        double lat2 = fLat;
        double lon1 = fLastLong;
        double lon2 = fLong;

        double lat = (lat1 + lat2) / 2 * 0.01745;
        double dx = 111.3 * Math.cos(lat) * (lon1 - lon2);
        double dy = 111.3 * (lat1 - lat2);

        double distance = Math.sqrt(dx * dx + dy * dy);

        fLen += Math.abs(distance);

        fLastLat = fLat;
        fLastLong = fLong;
    }

    return (float)fLen*1000; //einheit in meter
}