Package uk.co.mccombe.mapping

Class Datum

java.lang.Object
uk.co.mccombe.mapping.Datum
public class Datum extends 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

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final Datum
    AUG_7
    The Australian (1984) Geodetic Datum
    static final Datum
    ED_1950
    The European (1950) Datum
    static final Datum
    IRELAND_1965
    The Ireland (1965) Datum
    static final Datum
    MGI
     
    static final Datum
    MGI_SLOV
     
    static final Datum
    NTF
    The French NTF Datum (used in IGN/Lambert projections)
    static final Datum
    NZGD_1949
    The New Zealand 1949 Datum
    static final Datum
    NZGD_2000
    The New Zealand 2000 Datum
    static final Datum
    OSGB_1936
    The OSGB (1936) Datum - used as the Datum for UK Ordnance Survey mapping
    static final Datum
    WGS_1984
    The WGS (1984) Datum

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    Datum(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

    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
    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 Details

    • 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

    • MGI_SLOV

      public static final Datum MGI_SLOV

    • 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 Details

    • Datum

      protected Datum(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 Details

    • 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 String toString()
      Get name of Datum
      Overrides:
      toString in class Object
      Returns:
      Datum name