/* Copyright 2002-2025 CS GROUP
    * Licensed to CS GROUP (CS) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * CS licenses this file to You under the Apache License, Version 2.0
    * (the "License"); you may not use this file except in compliance with
    * the License.  You may obtain a copy of the License at
    *
    *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.orekit.files.ccsds.ndm.cdm;
  
  import org.hipparchus.linear.MatrixUtils;
  import org.hipparchus.linear.RealMatrix;
  import org.orekit.errors.OrekitException;
  import org.orekit.errors.OrekitMessages;
  import org.orekit.files.ccsds.section.CommentsContainer;
  
  /**
   * Container for XYZ covariance matrix data.
   * <p>
   * Beware that the Orekit getters and setters all rely on SI units. The parsers
   * and writers take care of converting these SI units into CCSDS mandatory units.
   * The {@link org.orekit.utils.units.Unit Unit} class provides useful
   * {@link org.orekit.utils.units.Unit#fromSI(double) fromSi} and
   * {@link org.orekit.utils.units.Unit#toSI(double) toSI} methods in case the callers
   * already use CCSDS units instead of the API SI units. The general-purpose
   * {@link org.orekit.utils.units.Unit Unit} class (without an 's') and the
   * CCSDS-specific {@link org.orekit.files.ccsds.definitions.Units Units} class
   * (with an 's') also provide some predefined units. These predefined units and the
   * {@link org.orekit.utils.units.Unit#fromSI(double) fromSi} and
   * {@link org.orekit.utils.units.Unit#toSI(double) toSI} conversion methods are indeed
   * what the parsers and writers use for the conversions.
   * </p>
   * <p>
   * This class as a RealMatrix as attribute which can be access with
   * {@code getXYZCovariaxMatrix} method. Beware that there are thus two ways to modify
   * the XYZ covariance : {@code setC…} ({@code setCxx}, {@code setCyx}…) which should be
   * prioritized and {@code getXYZCovariaxMatrix.setEntry(row, col, value)}.
   * </p>
   * <p>
   * The XYZ Covariance Matrix is only provided if {@link CdmMetadataKey#ALT_COV_TYPE} is
   * {@link AltCovarianceType#XYZ}, otherwise its terms will return {@code NaN}.
   * </p>
   * <p>
   * When available, the matrix is given in the 9×9 Lower Triangular Form. All parameters
   * of the 6×6 position/velocity submatrix are mandatory. The remaining elements will
   * return {@code NaN} if not provided.
   * </p>
   */
  public class XYZCovariance extends CommentsContainer {
  
      /** XYZ covariance matrix. */
      private final RealMatrix covarianceMatrix;
  
      /** Flag indicating whether the alternate covariance type set in the CDM Object metadata section is XYZ. */
      private final boolean covXYZset;
  
      /** Simple constructor. To update matrix value there are 2 ways to modify the XYZ
       * covariance : setC... ( setCxx, setCyx ...) which should be prioritized and
       * getXYZCovariaxMatrix.setEntry(row, col, value).
       * <p> The XYZ Covariance Matrix is only provided if {@link CdmMetadataKey#ALT_COV_TYPE} is {@link AltCovarianceType#XYZ}, otherwise
       * its terms will return NaN. </p>
       * <p> When available, the matrix is given in the 9×9 Lower Triangular Form. All parameters of the 6×6 position/velocity submatrix
       * are mandatory. The remaining elements will return NaN if not provided.</p>
       * @param covXYZset Flag indicating whether the alternate covariance type set in the CDM Object metadata section is XYZ.
       */
      public XYZCovariance(final boolean covXYZset) {
          this.covXYZset = covXYZset;
          covarianceMatrix = MatrixUtils.createRealMatrix(9, 9);
          for (int i = 0; i < covarianceMatrix.getRowDimension(); ++i) {
              for (int j = 0; j <= i; ++j) {
                  covarianceMatrix.setEntry(i, j, Double.NaN);
              }
          }
  
      }
  
      /** {@inheritDoc} */
      @Override
      public void validate(final double version) {
          super.validate(version);
  
          // Conditional on ALT_COV_TYPE = XYZ
          if (!isCovXYZset()) {
              throw new OrekitException(OrekitMessages.CCSDS_DATE_INVALID_PREAMBLE_FIELD, CdmMetadataKey.ALT_COV_TYPE);
          }
  
          // We only check values that are mandatory in a cdm file
          checkNotNaN(getCxx(),              XYZCovarianceKey.CX_X.name());
          checkNotNaN(getCyx(),              XYZCovarianceKey.CY_X.name());
          checkNotNaN(getCyy(),              XYZCovarianceKey.CY_Y.name());
          checkNotNaN(getCzx(),              XYZCovarianceKey.CZ_X.name());
         checkNotNaN(getCzy(),              XYZCovarianceKey.CZ_Y.name());
         checkNotNaN(getCzz(),              XYZCovarianceKey.CZ_Z.name());
         checkNotNaN(getCxdotx(),           XYZCovarianceKey.CXDOT_X.name());
         checkNotNaN(getCxdoty(),           XYZCovarianceKey.CXDOT_Y.name());
         checkNotNaN(getCxdotz(),           XYZCovarianceKey.CXDOT_Z.name());
         checkNotNaN(getCxdotxdot(),        XYZCovarianceKey.CXDOT_XDOT.name());
         checkNotNaN(getCydotx(),           XYZCovarianceKey.CYDOT_X.name());
         checkNotNaN(getCydoty(),           XYZCovarianceKey.CYDOT_Y.name());
         checkNotNaN(getCydotz(),           XYZCovarianceKey.CYDOT_Z.name());
         checkNotNaN(getCydotxdot(),        XYZCovarianceKey.CYDOT_XDOT.name());
         checkNotNaN(getCydotydot(),        XYZCovarianceKey.CYDOT_YDOT.name());
         checkNotNaN(getCzdotx(),           XYZCovarianceKey.CZDOT_X.name());
         checkNotNaN(getCzdoty(),           XYZCovarianceKey.CZDOT_Y.name());
         checkNotNaN(getCzdotz(),           XYZCovarianceKey.CZDOT_Z.name());
         checkNotNaN(getCzdotxdot(),        XYZCovarianceKey.CZDOT_XDOT.name());
         checkNotNaN(getCzdotydot(),        XYZCovarianceKey.CZDOT_YDOT.name());
         checkNotNaN(getCzdotzdot(),        XYZCovarianceKey.CZDOT_ZDOT.name());
     }
 
     /** Set an entry in the XYZ covariance matrix.
      * <p>
      * Both m(j, k) and m(k, j) are set.
      * </p>
      * @param j row index (must be between 0 and 5 (inclusive)
      * @param k column index (must be between 0 and 5 (inclusive)
      * @param entry value of the matrix entry
      */
     public void setCovarianceMatrixEntry(final int j, final int k, final double entry) {
         covarianceMatrix.setEntry(j, k, entry);
         covarianceMatrix.setEntry(k, j, entry);
     }
 
     /**
      * Get the XYZ covariance matrix.
      * <p> The XYZ Covariance Matrix is only provided if {@link CdmMetadataKey#ALT_COV_TYPE} is {@link AltCovarianceType#XYZ}, otherwise
      * its terms will return NaN. </p>
      * <p> When available, the matrix is given in the 9×9 Lower Triangular Form. All parameters of the 6×6 position/velocity submatrix
      * are mandatory. The remaining elements will return NaN if not provided.</p>
      * @return the XYZ covariance matrix
      */
     public RealMatrix getXYZCovarianceMatrix() {
         return covarianceMatrix;
     }
 
     /**
      * Get the object [1,1] in covariance matrix (with index starting at 1).
      * @return the object [1,1] in covariance matrix (in m²)
      */
     public double getCxx() {
         return covarianceMatrix.getEntry(0, 0);
     }
 
     /**
      * Set the object [1,1] in covariance matrix (with index starting at 1).
      * @param CXX = object [1,1] in covariance matrix (in m²)
      */
     public void setCxx(final double CXX) {
         refuseFurtherComments();
 
         // Conditional on ALT_COV_TYPE = XYZ
         if (!isCovXYZset()) {
             throw new OrekitException(OrekitMessages.CCSDS_DATE_INVALID_PREAMBLE_FIELD, CdmMetadataKey.ALT_COV_TYPE);
         }
 
         setCovarianceMatrixEntry(0, 0, CXX);
     }
 
     /**
      * Get the object [2,1] in covariance matrix (with index starting at 1).
      * @return the object [2,1] in covariance matrix (in m²)
      */
     public double getCyx() {
         return covarianceMatrix.getEntry(1, 0);
     }
 
     /**
      * Set the object [2,1] in covariance matrix (with index starting at 1).
      * @param CYX = object [2,1] in covariance matrix (in m²)
      */
     public void setCyx(final double CYX) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(1, 0, CYX);
     }
 
     /**
      * Get the object [2,2] in covariance matrix (with index starting at 1).
      * @return the object [2,2] in covariance matrix (in m²)
      */
     public double getCyy() {
         return covarianceMatrix.getEntry(1, 1);
     }
 
     /**
      * Set the object [2,2] in covariance matrix (with index starting at 1).
      * @param CYY = object [2,2] in covariance matrix (in m²)
      */
     public void setCyy(final double CYY) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(1, 1, CYY);
     }
 
     /**
      * Get the object [3,1] in covariance matrix (with index starting at 1).
      * @return the object [3,1] in covariance matrix (in m²)
      */
     public double getCzx() {
         return covarianceMatrix.getEntry(2, 0);
     }
 
     /**
      * Set the object [3,1] in covariance matrix (with index starting at 1).
      * @param CZX = object [3,1] in covariance matrix (in m²)
      */
     public void setCzx(final double CZX) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(2, 0, CZX);
     }
 
     /**
      * Get the object [3,2] in covariance matrix (with index starting at 1).
      * @return the object [3,2] in covariance matrix (in m²)
      */
     public double getCzy() {
         return covarianceMatrix.getEntry(2, 1);
     }
 
     /**
      * Set the object [3,2] in covariance matrix (with index starting at 1).
      * @param CZY = object [3,2] in covariance matrix (in m²)
      */
     public void setCzy(final double CZY) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(2, 1, CZY);
     }
 
     /**
      * Get the object [3,3] in covariance matrix (with index starting at 1).
      * @return the object [3,3] in covariance matrix (in m²)
      */
     public double getCzz() {
         return covarianceMatrix.getEntry(2, 2);
     }
 
     /**
      * Set the object [3,3] in covariance matrix (with index starting at 1).
      * @param CZZ = object [3,3] in covariance matrix (in m²)
      */
     public void setCzz(final double CZZ) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(2, 2, CZZ);
     }
 
     /**
      * Get the object [4,1] in covariance matrix (with index starting at 1).
      * @return the object [4,1] in covariance matrix (in m²/s)
      */
     public double getCxdotx() {
         return covarianceMatrix.getEntry(3, 0);
     }
 
     /**
      * Set the object [4,1] in covariance matrix (with index starting at 1).
      * @param CXdotX = object [4,1] in covariance matrix (in m²/s)
      */
     public void setCxdotx(final double CXdotX) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(3, 0, CXdotX);
     }
 
     /**
      * Get the object [4,2] in covariance matrix (with index starting at 1).
      * @return the object [4,2] in covariance matrix (in m²/s)
      */
     public double getCxdoty() {
         return covarianceMatrix.getEntry(3, 1);
     }
 
     /**
      * Set the object [4, 2] in covariance matrix (with index starting at 1).
      * @param CXdotY = object [4, 2] in covariance matrix (in m²/s)
      */
     public void setCxdoty(final double CXdotY) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(3, 1, CXdotY);
     }
 
     /**
      * Get the object [4, 3] in covariance matrix (with index starting at 1) .
      * @return the object [4, 3] in covariance matrix (in m²/s)
      */
     public double getCxdotz() {
         return covarianceMatrix.getEntry(3, 2);
     }
 
     /**
      * Set the object [4, 3] in covariance matrix (with index starting at 1).
      * @param CXdotZ = object [4,3] in covariance matrix (in m²/s)
      */
     public void setCxdotz(final double CXdotZ) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(3, 2, CXdotZ);
     }
 
     /**
      * Get the object [4, 4] in covariance matrix (with index starting at 1).
      * @return the object [4, 4] in covariance matrix (in m²/s²)
      */
     public double getCxdotxdot() {
         return covarianceMatrix.getEntry(3, 3);
     }
 
     /**
      * Set the object [4, 4] in covariance matrix (with index starting at 1).
      * @param CXdotXdot = object [4, 4] in covariance matrix (in m²/s²)
      */
     public void setCxdotxdot(final double CXdotXdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(3, 3, CXdotXdot);
     }
 
     /**
      * Get the object [5, 1] in covariance matrix (with index starting at 1).
      * @return the object [5, 1] in covariance matrix (in m²/s)
      */
     public double getCydotx() {
         return covarianceMatrix.getEntry(4, 0);
     }
 
     /**
      * Set the object [5,1] in covariance matrix (with index starting at 1).
      * @param CYdotX = object [5,1] in covariance matrix (in m²/s)
      */
     public void setCydotx(final double CYdotX) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(4, 0, CYdotX);
     }
 
     /**
      * Get the object [5,2] in covariance matrix (with index starting at 1).
      * @return the object [5,2] in covariance matrix (in m²/s)
      */
     public double getCydoty() {
         return covarianceMatrix.getEntry(4, 1);
     }
 
     /**
      * Set the object [5,2] in covariance matrix (with index starting at 1).
      * @param CYdotY = object [5,2] in covariance matrix (in m²/s)
      */
     public void setCydoty(final double CYdotY) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(4, 1, CYdotY);
     }
 
     /**
      * Get the object [5,3] in covariance matrix (with index starting at 1).
      * @return the object [5,3] in covariance matrix (in m²/s)
      */
     public double getCydotz() {
         return covarianceMatrix.getEntry(4, 2);
     }
 
     /**
      * Set the object [5,3] in covariance matrix (with index starting at 1).
      * @param CYdotZ = object [5,3] in covariance matrix (in m²/s)
      */
     public void setCydotz(final double CYdotZ) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(4, 2, CYdotZ);
     }
 
     /**
      * Get the object [5,4] in covariance matrix (with index starting at 1).
      * @return the object [5,4] in covariance matrix (in m²/s²)
      */
     public double getCydotxdot() {
         return covarianceMatrix.getEntry(4, 3);
     }
 
     /**
      * Set the object [5,4] in covariance matrix (with index starting at 1).
      * @param CYdotXdot = object [5,4] in covariance matrix (in m²/s²)
      */
     public void setCydotxdot(final double CYdotXdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(4, 3, CYdotXdot);
     }
 
     /**
      * Get the object [5,5] in covariance matrix (with index starting at 1).
      * @return the object [5,5] in covariance matrix (in m²/s²)
      */
     public double getCydotydot() {
         return covarianceMatrix.getEntry(4, 4);
     }
 
     /**
      * Set the object [5,5] in covariance matrix (with index starting at 1).
      * @param CYdotYdot = object [5,5] in covariance matrix (in m²/s²)
      */
     public void setCydotydot(final double CYdotYdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(4, 4, CYdotYdot);
     }
 
     /**
      * Get the object [6,1] in covariance matrix (with index starting at 1).
      * @return the object [6,1] in covariance matrix (in m²/s)
      */
     public double getCzdotx() {
         return covarianceMatrix.getEntry(5, 0);
     }
 
     /**
      * Set the object [6,1] in covariance matrix (with index starting at 1).
      * @param CZdotX = object [6,1] in covariance matrix (in m²/s)
      */
     public void setCzdotx(final double CZdotX) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(5, 0, CZdotX);
     }
 
     /**
      * Get the object [6,2] in covariance matrix (with index starting at 1).
      * @return the object [6,2] in covariance matrix (in m²/s)
      */
     public double getCzdoty() {
         return covarianceMatrix.getEntry(5, 1);
     }
 
     /**
      * Set the object [6,2] in covariance matrix (with index starting at 1).
      * @param CZdotY = object [6,2] in covariance matrix (in m²/s)
      */
     public void setCzdoty(final double CZdotY) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(5, 1, CZdotY);
     }
 
     /**
      * Get the object [6,3] in covariance matrix (with index starting at 1).
      * @return the object [6,3] in covariance matrix (in m²/s)
      */
     public double getCzdotz() {
         return covarianceMatrix.getEntry(5, 2);
     }
 
     /**
      * Set the object [6,3] in covariance matrix (with index starting at 1).
      * @param CZdotZ = object [6,3] in covariance matrix (in m²/s)
      */
     public void setCzdotz(final double CZdotZ) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(5, 2, CZdotZ);
     }
 
     /**
      * Get the object [6,4] in covariance matrix (with index starting at 1).
      * @return the object [6,4] in covariance matrix (in m²/s²)
      */
     public double getCzdotxdot() {
         return covarianceMatrix.getEntry(5, 3);
     }
 
     /**
      * Set the object [6,4] in covariance matrix (with index starting at 1).
      * @param CZdotXdot = object [6,4] in covariance matrix (in m²/s²)
      */
     public void setCzdotxdot(final double CZdotXdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(5, 3, CZdotXdot);
     }
 
     /**
      * Get the object [6,5] in covariance matrix (with index starting at 1).
      * @return the object [6,5] in covariance matrix (in m²/s²)
      */
     public double getCzdotydot() {
         return covarianceMatrix.getEntry(5, 4);
     }
 
     /**
      * Set the object [6,5] in covariance matrix (with index starting at 1).
      * @param CZdotYdot = object [6,5] in covariance matrix (in m²/s²)
      */
     public void setCzdotydot(final double CZdotYdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(5, 4, CZdotYdot);
     }
 
     /**
      * Get the object [6,6] in covariance matrix (with index starting at 1).
      * @return the object [6,6] in covariance matrix (in m²/s²)
      */
     public double getCzdotzdot() {
         return covarianceMatrix.getEntry(5, 5);
     }
 
     /**
      * Set the object [6,6] in covariance matrix (with index starting at 1).
      * @param CZdotZdot = object [6,6] in covariance matrix (in m²/s²)
      */
     public void setCzdotzdot(final double CZdotZdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(5, 5, CZdotZdot);
     }
 
     /**
      * Get the object [7,1] in covariance matrix (with index starting at 1).
      * @return the object [7,1] in covariance matrix (in m³/kg)
      */
     public double getCdrgx() {
         return covarianceMatrix.getEntry(6, 0);
     }
 
     /**
      * Set the object [7,1] in covariance matrix (with index starting at 1).
      * @param CDRGX = object [7,1] in covariance matrix (in m³/kg)
      */
     public void setCdrgx(final double CDRGX) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(6, 0, CDRGX);
     }
 
     /**
      * Get the object [7,2] in covariance matrix.
      * @return the object [7,2] in covariance matrix (in m³/kg)
      */
     public double getCdrgy() {
         return covarianceMatrix.getEntry(6, 1);
     }
 
     /**
      * Set the object [7,2] in covariance matrix (with index starting at 1).
      * @param CDRGY = object [7,2] in covariance matrix (in m³/kg)
      */
     public void setCdrgy(final double CDRGY) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(6, 1, CDRGY);
     }
 
     /**
      * Get the object [7,3] in covariance matrix (with index starting at 1).
      * @return the object [7,3] in covariance matrix (in m³/kg)
      */
     public double getCdrgz() {
         return covarianceMatrix.getEntry(6, 2);
     }
 
     /**
      * Set the object [7,3] in covariance matrix (with index starting at 1).
      * @param CDRGZ = object [7,3] in covariance matrix (in m³/kg)
      */
     public void setCdrgz(final double CDRGZ) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(6, 2, CDRGZ);
     }
 
     /**
      * Get the object [7,4] in covariance matrix (with index starting at 1).
      * @return the object [7,4] in covariance matrix (in m³/(kg.s))
      */
     public double getCdrgxdot() {
         return covarianceMatrix.getEntry(6, 3);
     }
 
     /**
      * Set the object [7,4] in covariance matrix (with index starting at 1).
      * @param CDRGXdot = object [7,4] in covariance matrix (in m³/(kg.s))
      */
     public void setCdrgxdot(final double CDRGXdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(6, 3, CDRGXdot);
     }
 
     /**
      * Get the object [7,5] in covariance matrix (with index starting at 1).
      * @return the object [7,5] in covariance matrix (in m³/(kg.s))
      */
     public double getCdrgydot() {
         return covarianceMatrix.getEntry(6, 4);
     }
 
     /**
      * Set the object [7,5] in covariance matrix (with index starting at 1).
      * @param CDRGYdot = object [7,5] in covariance matrix (in m³/(kg.s))
      */
     public void setCdrgydot(final double CDRGYdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(6, 4, CDRGYdot);
     }
 
     /**
      * Get the object [7,6] in covariance matrix (with index starting at 1).
      * @return the object [7,6] in covariance matrix (in m³/(kg.s))
      */
     public double getCdrgzdot() {
         return covarianceMatrix.getEntry(6, 5);
     }
 
     /**
      * Set the object [7,6] in covariance matrix (with index starting at 1).
      * @param CDRGZdot = object [7,6] in covariance matrix (in m³/(kg.s))
      */
     public void setCdrgzdot(final double CDRGZdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(6, 5, CDRGZdot);
     }
 
     /**
      * Get the object [7,7] in covariance matrix (with index starting at 1).
      * @return the object [7,7] in covariance matrix (in m⁴/kg²)
      */
     public double getCdrgdrg() {
         return covarianceMatrix.getEntry(6, 6);
     }
 
     /**
      * Set the object [7,7] in covariance matrix (with index starting at 1).
      * @param CDRGDRG = object [7,7] in covariance matrix (in m⁴/kg²)
      */
     public void setCdrgdrg(final double CDRGDRG) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(6, 6, CDRGDRG);
     }
 
     /**
      * Get the object [8,1] in covariance matrix (with index starting at 1).
      * @return the object [8,1] in covariance matrix (in m³/kg)
      */
     public double getCsrpx() {
         return covarianceMatrix.getEntry(7, 0);
     }
 
     /**
      * Set the object [8,1] in covariance matrix (with index starting at 1).
      * @param CSRPX = object [8,1] in covariance matrix (in m³/kg)
      */
     public void setCsrpx(final double CSRPX) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(7, 0, CSRPX);
     }
 
     /**
      * Get the object [8,2] in covariance matrix (with index starting at 1).
      * @return the object [8,2] in covariance matrix (in m³/kg)
      */
     public double getCsrpy() {
         return covarianceMatrix.getEntry(7, 1);
     }
 
     /**
      * Set the object [8,2] in covariance matrix (with index starting at 1).
      * @param CSRPY = object [8,2] in covariance matrix (in m³/kg)
      */
     public void setCsrpy(final double CSRPY) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(7, 1, CSRPY);
     }
 
     /**
      * Get the object [8,3] in covariance matrix (with index starting at 1).
      * @return the object [8,3] in covariance matrix (in m³/kg)
      */
     public double getCsrpz() {
         return covarianceMatrix.getEntry(7, 2);
     }
 
     /**
      * Set the object [8,3] in covariance matrix (with index starting at 1).
      * @param CSRPZ = object [8,3] in covariance matrix (in m³/kg)
      */
     public void setCsrpz(final double CSRPZ) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(7, 2, CSRPZ);
     }
 
     /**
      * Get the object [8,4] in covariance matrix (with index starting at 1).
      * @return the object [8,4] in covariance matrix (in m³/(kg.s))
      */
     public double getCsrpxdot() {
         return covarianceMatrix.getEntry(7, 3);
     }
 
     /**
      * Set the object [8,4] in covariance matrix (with index starting at 1).
      * @param CSRPXdot = object [8,4] in covariance matrix (in m³/(kg.s))
      */
     public void setCsrpxdot(final double CSRPXdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(7, 3, CSRPXdot);
     }
 
     /**
      * Get the object [8,5] in covariance matrix (with index starting at 1).
      * @return the object [8,5] in covariance matrix (in m³/(kg.s))
      */
     public double getCsrpydot() {
         return covarianceMatrix.getEntry(7, 4);
     }
 
     /**
      * Set the object [8,5] in covariance matrix (with index starting at 1).
      * @param CSRPYdot = object [8,5] in covariance matrix (in m³/(kg.s))
      */
     public void setCsrpydot(final double CSRPYdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(7, 4, CSRPYdot);
     }
 
     /**
      * Get the object [8,6] in covariance matrix (with index starting at 1).
      * @return the object [8,6] in covariance matrix (in m³/(kg.s))
      */
     public double getCsrpzdot() {
         return covarianceMatrix.getEntry(7, 5);
     }
 
     /**
      * Set the object [8,6] in covariance matrix (with index starting at 1).
      * @param CSRPZdot = object [8,6] in covariance matrix (in m³/(kg.s))
      */
     public void setCsrpzdot(final double CSRPZdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(7, 5, CSRPZdot);
     }
 
     /**
      * Get the object [8,7] in covariance matrix (with index starting at 1).
      * @return the object [8,7] in covariance matrix (in m⁴/kg²)
      */
     public double getCsrpdrg() {
         return covarianceMatrix.getEntry(7, 6);
     }
 
     /**
      * Set the object [8,7] in covariance matrix (with index starting at 1).
      * @param CSRPDRG = object [8,7] in covariance matrix (in m⁴/kg²)
      */
     public void setCsrpdrg(final double CSRPDRG) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(7, 6, CSRPDRG);
     }
 
     /**
      * Get the object [8,8] in covariance matrix (with index starting at 1).
      * @return the object [8,8] in covariance matrix (in m⁴/kg²)
      */
     public double getCsrpsrp() {
         return covarianceMatrix.getEntry(7, 7);
     }
 
     /**
      * Set the object [8,8] in covariance matrix (with index starting at 1).
      * @param CSRPSRP = object [8,8] in covariance matrix (in m⁴/kg²)
      */
     public void setCsrpsrp(final double CSRPSRP) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(7, 7, CSRPSRP);
     }
 
     /**
      * Get the object [9,1] in covariance matrix (with index starting at 1).
      * @return the object [9,1] in covariance matrix (in m²/s²)
      */
     public double getCthrx() {
         return covarianceMatrix.getEntry(8, 0);
     }
 
     /**
      * Set the object [9,1] in covariance matrix (with index starting at 1).
      * @param CTHRX = object [9,1] in covariance matrix (in m²/s²)
      */
     public void setCthrx(final double CTHRX) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(8, 0, CTHRX);
     }
 
     /**
      * Get the object [9,2] in covariance matrix (with index starting at 1).
      * @return the object [9,2] in covariance matrix (in m²/s²)
      */
     public double getCthry() {
         return covarianceMatrix.getEntry(8, 1);
     }
 
     /**
      * Set the object [9,2] in covariance matrix (with index starting at 1).
      * @param CTHRY = object [9,2] in covariance matrix (in m²/s²)
      */
     public void setCthry(final double CTHRY) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(8, 1, CTHRY);
     }
 
     /**
      * Get the object [9,3] in covariance matrix (with index starting at 1).
      * @return the object [9,3] in covariance matrix (in m²/s²)
      */
     public double getCthrz() {
         return covarianceMatrix.getEntry(8, 2);
     }
 
     /**
      * Set the object [9,3] in covariance matrix (with index starting at 1).
      * @param CTHRZ = object [9,3] in covariance matrix (in m²/s²)
      */
     public void setCthrz(final double CTHRZ) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(8, 2, CTHRZ);
     }
 
     /**
      * Get the object [9,4] in covariance matrix (with index starting at 1).
      * @return the object [9,4] in covariance matrix (in m²/s³)
      */
     public double getCthrxdot() {
         return covarianceMatrix.getEntry(8, 3);
     }
 
     /**
      * Set the object [9,4] in covariance matrix (with index starting at 1).
      * @param CTHRXdot = object [9,4] in covariance matrix (in m²/s³)
      */
     public void setCthrxdot(final double CTHRXdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(8, 3, CTHRXdot);
     }
 
     /**
      * Get the object [9,5] in covariance matrix (with index starting at 1).
      * @return the object [9,5] in covariance matrix (in m²/s³)
      */
     public double getCthrydot() {
         return covarianceMatrix.getEntry(8, 4);
     }
 
     /**
      * Set the object [9,5] in covariance matrix (with index starting at 1).
      * @param CTHRYdot = object [9,5] in covariance matrix (in m²/s³)
      */
     public void setCthrydot(final double CTHRYdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(8, 4, CTHRYdot);
     }
 
     /**
      * Get the object [9,6] in covariance matrix (with index starting at 1).
      * @return the object [9,6] in covariance matrix (in m²/s³)
      */
     public double getCthrzdot() {
         return covarianceMatrix.getEntry(8, 5);
     }
 
     /**
      * Set the object [9,6] in covariance matrix (with index starting at 1).
      * @param CTHRZdot = object [9,6] in covariance matrix (in m²/s³)
      */
     public void setCthrzdot(final double CTHRZdot) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(8, 5, CTHRZdot);
     }
 
     /**
      * Get the object [9,7] in covariance matrix (with index starting at 1).
      * @return the object [9,7] in covariance matrix (in m³/(kg.s²))
      */
     public double getCthrdrg() {
         return covarianceMatrix.getEntry(8, 6);
     }
 
     /**
      * Set the object [9,7] in covariance matrix (with index starting at 1).
      * @param CTHRDRG = object [9,7] in covariance matrix (in m³/(kg.s²))
      */
     public void setCthrdrg(final double CTHRDRG) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(8, 6, CTHRDRG);
     }
 
     /**
      * Get the object [9,8] in covariance matrix (with index starting at 1).
      * @return the object [9,8] in covariance matrix (in m³/(kg.s²))
      */
     public double getCthrsrp() {
         return covarianceMatrix.getEntry(8, 7);
     }
 
     /**
      * Set the object [9,8] in covariance matrix (with index starting at 1).
      * @param CTHRSRP = object [9,8] in covariance matrix (in m³/(kg.s²))
      */
     public void setCthrsrp(final double CTHRSRP) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(8, 7, CTHRSRP);
     }
 
     /**
      * Get the object [9,9] in covariance matrix (with index starting at 1).
      * @return the object [9,9] in covariance matrix (in m²/s⁴)
      */
     public double getCthrthr() {
         return covarianceMatrix.getEntry(8, 8);
     }
 
     /**
      * Set the object [9,9] in covariance matrix (with index starting at 1).
      * @param CTHRTHR = object [9,9] in covariance matrix (in m²/s⁴)
      */
     public void setCthrthr(final double CTHRTHR) {
         refuseFurtherComments();
         setCovarianceMatrixEntry(8, 8, CTHRTHR);
     }
 
     /** Get the flag indicating whether the alternate covariance type set in the CDM Object metadata section is XYZ.
      * @return the covXYZset
      */
     public boolean isCovXYZset() {
         return covXYZset;
     }
 }