mccombe.mapping
Class Datum

java.lang.Object
  extended by mccombe.mapping.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


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