Class Datum


  • public class Datum
    extends java.lang.Object

    Datum is the base class for a coordinate system datum. Sub-classes need to define values for the seven Helmert parameters needed to translate to the Datum FROM WGS-84

    An extensive list of Helmert parameters can be found at http://earth-info.nga.mil/GandG/coordsys/datums/helmert.html Units are

      s - ppm
      rx, ry, rz - seconds of arc. 
      tx, ty, tz - metres
     

    This class also defines a set of static final member instances for common Datums

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      protected Datum​(java.lang.String name, double tx, double ty, double tz, double rotx, double roty, double rotz, double scale)
      Create an instance of Datum using Helmert coefficients in abstract methods
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      XYZ fromWGS84​(XYZ from)
      Converts XYZ coordinates from WGS-84 to this datum using Helmert Transformation
      double rx()
      Get rotation about X
      double ry()
      Get Y rotation
      double rz()
      Get Z rotation
      double s()
      Get scale factor adjustment
      java.lang.String toString()
      Get name of Datum
      XYZ toWGS84​(XYZ to)
      Convert XYZ Coordinates referred to this datum to WGS-84
      double tx()
      Get X translation
      double ty()
      Get Y translation
      double tz()
      Get Z translation
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
    • Field Detail

      • ED_1950

        public static final Datum ED_1950
        The European (1950) Datum
      • IRELAND_1965

        public static final Datum IRELAND_1965
        The Ireland (1965) Datum
      • NTF

        public static final Datum NTF
        The French NTF Datum (used in IGN/Lambert projections)
      • OSGB_1936

        public static final Datum OSGB_1936
        The OSGB (1936) Datum - used as the Datum for UK Ordnance Survey mapping
      • WGS_1984

        public static final Datum WGS_1984
        The WGS (1984) Datum
      • AUG_7

        public static final Datum AUG_7
        The Australian (1984) Geodetic Datum
      • MGI

        public static final Datum MGI
      • NZGD_1949

        public static final Datum NZGD_1949
        The New Zealand 1949 Datum
      • NZGD_2000

        public static final Datum NZGD_2000
        The New Zealand 2000 Datum
    • Constructor Detail

      • Datum

        protected Datum​(java.lang.String name,
                        double tx,
                        double ty,
                        double tz,
                        double rotx,
                        double roty,
                        double rotz,
                        double scale)
        Create an instance of Datum using Helmert coefficients in abstract methods
    • Method Detail

      • fromWGS84

        public XYZ fromWGS84​(XYZ from)
        Converts XYZ coordinates from WGS-84 to this datum using Helmert Transformation
        Parameters:
        from - XYZ Coordinates referred to WGS-84
        Returns:
        XYZ Coordinates referred to this datum
      • toWGS84

        public XYZ toWGS84​(XYZ to)
        Convert XYZ Coordinates referred to this datum to WGS-84
        Parameters:
        to - XYZ Coordinates to convert
        Returns:
        XYZ Coordinates referred to WGS-84
      • tx

        public double tx()
        Get X translation
        Returns:
        X translation
      • ty

        public double ty()
        Get Y translation
        Returns:
        Y translation
      • tz

        public double tz()
        Get Z translation
        Returns:
        Z Translation
      • rx

        public double rx()
        Get rotation about X
        Returns:
        X rotation
      • ry

        public double ry()
        Get Y rotation
        Returns:
        Y rotation
      • rz

        public double rz()
        Get Z rotation
        Returns:
        Z rotation
      • s

        public double s()
        Get scale factor adjustment
        Returns:
        Scale factor adjustment (ppm)
      • toString

        public java.lang.String toString()
        Get name of Datum
        Overrides:
        toString in class java.lang.Object
        Returns:
        Datum name