Package org.geotools.referencing.datum

Class 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:
    Serialized Form

    • Field Detail

      • 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 Detail

      • BursaWolfParameters

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

    • Method Detail

      • 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.

      • 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.