Package org.geotools.referencing.datum

Class BursaWolfParameters

Object
Formattable
BursaWolfParameters
All Implemented Interfaces:
Serializable, Cloneable, Cloneable
public class BursaWolfParameters extends Formattable implements Cloneable, Serializable
Parameters for a geographic transformation between two datum. The Bursa Wolf parameters should be applied to geocentric coordinates, where the X axis points towards the Greenwich Prime Meridian, the Y axis points East, and the Z axis points North. The "Bursa-Wolf" formula is expressed in matrix form with 7 parameters:

Since:
2.1
Author:
Martin Desruisseaux (IRD)
See Also:

  • Field Details

    • dx

      public double dx
      Bursa Wolf shift in meters.

    • dy

      public double dy
      Bursa Wolf shift in meters.

    • dz

      public double dz
      Bursa Wolf shift in meters.

    • ex

      public double ex
      Bursa Wolf rotation in arc seconds.

    • ey

      public double ey
      Bursa Wolf rotation in arc seconds.

    • ez

      public double ez
      Bursa Wolf rotation in arc seconds.

    • ppm

      public double ppm
      Bursa Wolf scaling in parts per million.

    • targetDatum

      public final GeodeticDatum targetDatum
      The target datum for this parameters.

  • Constructor Details

    • BursaWolfParameters

      public BursaWolfParameters(GeodeticDatum target)
      Constructs a transformation info with all parameters set to 0.
      Parameters:
      target - The target datum for this parameters.

  • Method Details

    • isIdentity

      public boolean isIdentity()
      Returns true if this Bursa Wolf parameters performs no operation. This is true when all parameters are set to zero.
      Returns:
      true if the parameters describe no operation.

    • isTranslation

      public boolean isTranslation()
      Returns true if this Bursa Wolf parameters contains only translation terms.
      Returns:
      true if the parameters describe to a translation only.

    • getAffineTransform

      public XMatrix getAffineTransform()
      Returns an affine transform that can be used to define this Bursa Wolf transformation. The formula is as follows: 
       S = 1 + ppm/1000000

 [ X’ ]    [     S   -ez*S   +ey*S   dx ]  [ X ]
 [ Y’ ]  = [ +ez*S       S   -ex*S   dy ]  [ Y }
 [ Z’ ]    [ -ey*S   +ex*S       S   dz ]  [ Z ]
 [ 1  ]    [     0       0       0    1 ]  [ 1 ]
      This affine transform can be applied on geocentric coordinates.
      Returns:
      An affine transform created from the parameters.

    • setAffineTransform

      public void setAffineTransform(Matrix matrix, double eps) throws IllegalArgumentException
      Sets transformation info from the specified matrix, which must be affine. In addition, the matrix minus the last row and last column must be antisymmetric.
      Parameters:
      matrix - The matrix to fit as a Bursa-Wolf construct.
      eps - The tolerance error for the antisymmetric matrix test. Should be a small number like 1E-4.
      Throws:
      IllegalArgumentException - if the specified matrix doesn't meet the conditions.
      Since:
      2.2

    • hashCode

      public int hashCode()
      Returns a hash value for this object.
      Overrides:
      hashCode in class Object
      Returns:
      The hash code value. This value doesn't need to be the same in past or future versions of this class.

    • clone

      public BursaWolfParameters clone()
      Returns a copy of this object.
      Specified by:
      clone in interface Cloneable
      Overrides:
      clone in class Object
      Returns:
      A clone of the parameters.
      See Also:

    • equals

      public boolean equals(Object object)
      Compares the specified object with this object for equality.
      Overrides:
      equals in class Object
      Parameters:
      object - The object to compare with the parameters.
      Returns:
      true if the given object is equals to the parameters.

    • formatWKT

      protected String formatWKT(Formatter formatter)
      Format the inner part of a Well Known Text (WKT) element. The WKT contains the parameters in translation, rotation, scale order, as in TOWGS84[dx, dy, dz, ex, ey, ez, ppm].
      Overrides:
      formatWKT in class Formattable
      Parameters:
      formatter - The formatter to use.
      Returns:
      The WKT element name.
      See Also: