How to use

getPositionVectorTransformation

method

in

org.apache.sis.referencing.datum.BursaWolfParameters

/**
 * Invokes {@link BursaWolfParameters#getPositionVectorTransformation(Date)} for a date calculated from
 * the temporal elements on the given extent.  This method chooses an instant located midway between the
 * start and end time.
 */
private static Matrix createTransformation(final BursaWolfParameters bursaWolf, final Extent areaOfInterest) {
  /*
   * Implementation note: we know that we do not need to compute an instant if the parameters is
   * not a subclass of BursaWolfParameters. This optimisation covers the vast majority of cases.
   */
  return bursaWolf.getPositionVectorTransformation(bursaWolf.getClass() != BursaWolfParameters.class ?
      Extents.getDate(areaOfInterest, 0.5) : null);       // 0.5 is for choosing midway instant.
}

/**
 * Invokes {@link BursaWolfParameters#getPositionVectorTransformation(Date)} for a date calculated from
 * the temporal elements on the given extent.  This method chooses an instant located midway between the
 * start and end time.
 */
private static Matrix createTransformation(final BursaWolfParameters bursaWolf, final Extent areaOfInterest) {
  /*
   * Implementation note: we know that we do not need to compute an instant if the parameters is
   * not a subclass of BursaWolfParameters. This optimisation covers the vast majority of cases.
   */
  return bursaWolf.getPositionVectorTransformation(bursaWolf.getClass() != BursaWolfParameters.class ?
      Extents.getDate(areaOfInterest, 0.5) : null);       // 0.5 is for choosing midway instant.
}

/**
 * Invokes {@link BursaWolfParameters#getPositionVectorTransformation(Date)}
 * and compares with our own matrix calculated using double arithmetic.
 */
private static MatrixSIS getPositionVectorTransformation(final BursaWolfParameters p) {
  final double   S = 1 + p.dS / BursaWolfParameters.PPM;
  final double  RS = TO_RADIANS * S;
  final Matrix4 expected = new Matrix4(
        S,  -p.rZ*RS,  +p.rY*RS,  p.tX,
    +p.rZ*RS,         S,  -p.rX*RS,  p.tY,
    -p.rY*RS,  +p.rX*RS,         S,  p.tZ,
        0,         0,         0,  1);
  final MatrixSIS matrix = MatrixSIS.castOrCopy(p.getPositionVectorTransformation(null));
  assertMatrixEquals("getPositionVectorTransformation", expected, matrix, p.isTranslation() ? 0 : 1E-14);
  return matrix;
}

  parameters.reverseRotation();
return MathTransforms.linear(parameters.getPositionVectorTransformation(null));

  parameters.reverseRotation();
return MathTransforms.linear(parameters.getPositionVectorTransformation(null));

/**
 * Tests the {@link BursaWolfParameters#setPositionVectorTransformation(Matrix, double)} method.
 * This is an internal consistency test.
 */
@Test
@DependsOnMethod("testGetPositionVectorTransformation")
public void testSetPositionVectorTransformation() {
  final BursaWolfParameters bursaWolf = createED87_to_WGS84();
  final Matrix matrix = bursaWolf.getPositionVectorTransformation(null);
  final BursaWolfParameters actual = new BursaWolfParameters(
      bursaWolf.getTargetDatum(), bursaWolf.getDomainOfValidity());
  actual.setPositionVectorTransformation(matrix, 1E-10);
  assertEquals(bursaWolf, actual);
}