Commit 5b39b454 authored by Luc Maisonobe's avatar Luc Maisonobe
Browse files

Added the code for tutorials.

parent cd7c5806
/* Copyright 2013-2015 CS Systèmes d'Information
* Licensed to CS Systèmes d'Information (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 fr.cs.examples;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import org.apache.commons.math3.geometry.euclidean.threed.Rotation;
import org.apache.commons.math3.geometry.euclidean.threed.Vector3D;
import org.apache.commons.math3.util.FastMath;
import org.orekit.bodies.GeodeticPoint;
import org.orekit.data.DataProvidersManager;
import org.orekit.data.DirectoryCrawler;
import org.orekit.errors.OrekitException;
import org.orekit.frames.Frame;
import org.orekit.frames.FramesFactory;
import org.orekit.frames.Transform;
import org.orekit.rugged.api.AlgorithmId;
import org.orekit.rugged.api.BodyRotatingFrameId;
import org.orekit.rugged.api.EllipsoidId;
import org.orekit.rugged.api.InertialFrameId;
import org.orekit.rugged.api.Rugged;
import org.orekit.rugged.api.RuggedBuilder;
import org.orekit.rugged.errors.RuggedException;
import org.orekit.rugged.linesensor.LineSensor;
import org.orekit.rugged.linesensor.LinearLineDatation;
import org.orekit.rugged.los.LOSBuilder;
import org.orekit.rugged.los.FixedRotation;
import org.orekit.rugged.los.TimeDependentLOS;
import org.orekit.rugged.utils.ParameterType;
import org.orekit.time.AbsoluteDate;
import org.orekit.time.TimeScale;
import org.orekit.time.TimeScalesFactory;
import org.orekit.utils.AngularDerivativesFilter;
import org.orekit.utils.CartesianDerivativesFilter;
import org.orekit.utils.IERSConventions;
import org.orekit.utils.PVCoordinates;
import org.orekit.utils.TimeStampedAngularCoordinates;
import org.orekit.utils.TimeStampedPVCoordinates;
public class DirectLocation {
public static void main(String[] args) {
try {
// Initialize Orekit, assuming an orekit-data folder is in user home directory
File home = new File(System.getProperty("user.home"));
File orekitData = new File(home, "orekit-data");
DataProvidersManager.getInstance().addProvider(new DirectoryCrawler(orekitData));
// The raw viewing direction of pixel i with respect to the instrument is defined by the vector:
List<Vector3D> rawDirs = new ArrayList<Vector3D>();
for (int i = 0; i < 2000; i++) {
//20° field of view, 2000 pixels
rawDirs.add(new Vector3D(0d, i*FastMath.toRadians(20)/2000d, 1d));
}
// The instrument is oriented 10° off nadir around the X-axis, we need to rotate the viewing
// direction to obtain the line of sight in the satellite frame
LOSBuilder losBuilder = new LOSBuilder(rawDirs);
losBuilder.addTransform(new FixedRotation(ParameterType.FIXED, Vector3D.PLUS_I, FastMath.toRadians(10)));
TimeDependentLOS lineOfSight = losBuilder.build();
// We use Orekit for handling time and dates, and Rugged for defining the datation model:
TimeScale gps = TimeScalesFactory.getGPS();
AbsoluteDate absDate = new AbsoluteDate("2009-12-11T16:59:30.0", gps);
LinearLineDatation lineDatation = new LinearLineDatation(absDate, 1d, 20);
// With the LOS and the datation now defined , we can initialize a line sensor object in Rugged:
LineSensor lineSensor = new LineSensor("mySensor", lineDatation, Vector3D.ZERO, lineOfSight);
// In our application, we simply need to know the name of the frames we are working with. Positions and
// velocities are given in the ITRF terrestrial frame, while the quaternions are given in EME2000
// inertial frame.
Frame eme2000 = FramesFactory.getEME2000();
boolean simpleEOP = true; // we don't want to compute tiny tidal effects at millimeter level
Frame itrf = FramesFactory.getITRF(IERSConventions.IERS_2010, simpleEOP);
ArrayList<TimeStampedAngularCoordinates> satelliteQList = new ArrayList<TimeStampedAngularCoordinates>();
ArrayList<TimeStampedPVCoordinates> satellitePVList = new ArrayList<TimeStampedPVCoordinates>();
addSatelliteQ(gps, satelliteQList, "2009-12-11T16:58:42.592937", -0.340236d, 0.333952d, -0.844012d, -0.245684d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T16:59:06.592937", -0.354773d, 0.329336d, -0.837871d, -0.252281d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T16:59:30.592937", -0.369237d, 0.324612d, -0.831445d, -0.258824d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T16:59:54.592937", -0.3836d, 0.319792d, -0.824743d, -0.265299d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:00:18.592937", -0.397834d, 0.314883d, -0.817777d, -0.271695d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:00:42.592937", -0.411912d, 0.309895d, -0.810561d, -0.278001d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:01:06.592937", -0.42581d, 0.304838d, -0.803111d, -0.284206d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:01:30.592937", -0.439505d, 0.299722d, -0.795442d, -0.290301d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:01:54.592937", -0.452976d, 0.294556d, -0.787571d, -0.296279d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:02:18.592937", -0.466207d, 0.28935d, -0.779516d, -0.302131d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T16:58:42.592937", -726361.466d, -5411878.485d, 4637549.599d, -2068.995d, -4500.601d, -5576.736d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T16:59:04.192937", -779538.267d, -5506500.533d, 4515934.894d, -2058.308d, -4369.521d, -5683.906d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T16:59:25.792937", -832615.368d, -5598184.195d, 4392036.13d, -2046.169d, -4236.279d, -5788.201d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T16:59:47.392937", -885556.748d, -5686883.696d, 4265915.971d, -2032.579d, -4100.944d, -5889.568d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:00:08.992937", -938326.32d, -5772554.875d, 4137638.207d, -2017.537d, -3963.59d, -5987.957d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:00:30.592937", -990887.942d, -5855155.21d, 4007267.717d, -2001.046d, -3824.291d, -6083.317d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:00:52.192937", -1043205.448d, -5934643.836d, 3874870.441d, -1983.107d, -3683.122d, -6175.6d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:01:13.792937", -1095242.669d, -6010981.571d, 3740513.34d, -1963.723d, -3540.157d, -6264.76d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:01:35.392937", -1146963.457d, -6084130.93d, 3604264.372d, -1942.899d, -3395.473d, -6350.751d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:01:56.992937", -1198331.706d, -6154056.146d, 3466192.446d, -1920.64d, -3249.148d, -6433.531d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:02:18.592937", -1249311.381d, -6220723.191d, 3326367.397d, -1896.952d, -3101.26d, -6513.056d);
Rugged rugged = new RuggedBuilder().
setAlgorithm(AlgorithmId.IGNORE_DEM_USE_ELLIPSOID).
setEllipsoid(EllipsoidId.WGS84, BodyRotatingFrameId.ITRF).
setTimeSpan(absDate, absDate.shiftedBy(60.0), 0.01, 5 / lineSensor.getRate(0)).
setTrajectory(InertialFrameId.EME2000,
satellitePVList, 4, CartesianDerivativesFilter.USE_P,
satelliteQList, 4, AngularDerivativesFilter.USE_R).
addLineSensor(lineSensor).
build();
Vector3D position = lineSensor.getPosition(); // This returns a zero vector since we set the relative position of the sensor w.r.T the satellite to 0.
AbsoluteDate firstLineDate = lineSensor.getDate(0);
Vector3D los = lineSensor.getLos(firstLineDate, 0);
GeodeticPoint upLeftPoint = rugged.directLocation(firstLineDate, position, los);
System.out.format(Locale.US, "upper left point: φ = %8.3f °, λ = %8.3f °, h = %8.3f m%n",
FastMath.toDegrees(upLeftPoint.getLatitude()),
FastMath.toDegrees(upLeftPoint.getLongitude()),
upLeftPoint.getAltitude());
} catch (OrekitException oe) {
System.err.println(oe.getLocalizedMessage());
System.exit(1);
} catch (RuggedException re) {
System.err.println(re.getLocalizedMessage());
System.exit(1);
}
}
private static void addSatellitePV(TimeScale gps, Frame eme2000, Frame itrf,
ArrayList<TimeStampedPVCoordinates> satellitePVList,
String absDate,
double px, double py, double pz, double vx, double vy, double vz)
throws OrekitException {
AbsoluteDate ephemerisDate = new AbsoluteDate(absDate, gps);
Vector3D position = new Vector3D(px, py, pz);
Vector3D velocity = new Vector3D(vx, vy, vz);
PVCoordinates pvITRF = new PVCoordinates(position, velocity);
Transform transform = itrf.getTransformTo(eme2000, ephemerisDate);
Vector3D pEME2000 = transform.transformPosition(pvITRF.getPosition());
Vector3D vEME2000 = transform.transformVector(pvITRF.getVelocity());
satellitePVList.add(new TimeStampedPVCoordinates(ephemerisDate, pEME2000, vEME2000, Vector3D.ZERO));
}
private static void addSatelliteQ(TimeScale gps, ArrayList<TimeStampedAngularCoordinates> satelliteQList, String absDate,
double q0, double q1, double q2, double q3) {
AbsoluteDate attitudeDate = new AbsoluteDate(absDate, gps);
Rotation rotation = new Rotation(q0, q1, q2, q3, true);
TimeStampedAngularCoordinates pair =
new TimeStampedAngularCoordinates(attitudeDate, rotation, Vector3D.ZERO, Vector3D.ZERO);
satelliteQList.add(pair);
}
}
/* Copyright 2013-2015 CS Systèmes d'Information
* Licensed to CS Systèmes d'Information (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 fr.cs.examples;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import org.apache.commons.math3.geometry.euclidean.threed.Rotation;
import org.apache.commons.math3.geometry.euclidean.threed.Vector3D;
import org.apache.commons.math3.util.FastMath;
import org.orekit.bodies.GeodeticPoint;
import org.orekit.data.DataProvidersManager;
import org.orekit.data.DirectoryCrawler;
import org.orekit.errors.OrekitException;
import org.orekit.frames.Frame;
import org.orekit.frames.FramesFactory;
import org.orekit.frames.Transform;
import org.orekit.rugged.api.AlgorithmId;
import org.orekit.rugged.api.BodyRotatingFrameId;
import org.orekit.rugged.api.EllipsoidId;
import org.orekit.rugged.api.InertialFrameId;
import org.orekit.rugged.api.Rugged;
import org.orekit.rugged.api.RuggedBuilder;
import org.orekit.rugged.errors.RuggedException;
import org.orekit.rugged.linesensor.LineSensor;
import org.orekit.rugged.linesensor.LinearLineDatation;
import org.orekit.rugged.los.LOSBuilder;
import org.orekit.rugged.los.FixedRotation;
import org.orekit.rugged.los.TimeDependentLOS;
import org.orekit.rugged.raster.TileUpdater;
import org.orekit.rugged.raster.UpdatableTile;
import org.orekit.rugged.utils.ParameterType;
import org.orekit.time.AbsoluteDate;
import org.orekit.time.TimeScale;
import org.orekit.time.TimeScalesFactory;
import org.orekit.utils.AngularDerivativesFilter;
import org.orekit.utils.CartesianDerivativesFilter;
import org.orekit.utils.Constants;
import org.orekit.utils.IERSConventions;
import org.orekit.utils.PVCoordinates;
import org.orekit.utils.TimeStampedAngularCoordinates;
import org.orekit.utils.TimeStampedPVCoordinates;
public class DirectLocationWithDEM {
public static void main(String[] args) {
try {
// Initialize Orekit, assuming an orekit-data folder is in user home directory
File home = new File(System.getProperty("user.home"));
File orekitData = new File(home, "orekit-data");
DataProvidersManager.getInstance().addProvider(new DirectoryCrawler(orekitData));
// The raw viewing direction of pixel i with respect to the instrument is defined by the vector:
List<Vector3D> rawDirs = new ArrayList<Vector3D>();
for (int i = 0; i < 2000; i++) {
//20° field of view, 2000 pixels
rawDirs.add(new Vector3D(0d, i*FastMath.toRadians(20)/2000d, 1d));
}
// The instrument is oriented 10° off nadir around the X-axis, we need to rotate the viewing
// direction to obtain the line of sight in the satellite frame
LOSBuilder losBuilder = new LOSBuilder(rawDirs);
losBuilder.addTransform(new FixedRotation(ParameterType.FIXED, Vector3D.PLUS_I, FastMath.toRadians(10)));
TimeDependentLOS lineOfSight = losBuilder.build();
// We use Orekit for handling time and dates, and Rugged for defining the datation model:
TimeScale gps = TimeScalesFactory.getGPS();
AbsoluteDate absDate = new AbsoluteDate("2009-12-11T16:59:30.0", gps);
LinearLineDatation lineDatation = new LinearLineDatation(absDate, 1d, 20);
// With the LOS and the datation now defined , we can initialize a line sensor object in Rugged:
LineSensor lineSensor = new LineSensor("mySensor", lineDatation, Vector3D.ZERO, lineOfSight);
// In our application, we simply need to know the name of the frames we are working with. Positions and
// velocities are given in the ITRF terrestrial frame, while the quaternions are given in EME2000
// inertial frame.
Frame eme2000 = FramesFactory.getEME2000();
boolean simpleEOP = true; // we don't want to compute tiny tidal effects at millimeter level
Frame itrf = FramesFactory.getITRF(IERSConventions.IERS_2010, simpleEOP);
ArrayList<TimeStampedAngularCoordinates> satelliteQList = new ArrayList<TimeStampedAngularCoordinates>();
ArrayList<TimeStampedPVCoordinates> satellitePVList = new ArrayList<TimeStampedPVCoordinates>();
addSatelliteQ(gps, satelliteQList, "2009-12-11T16:58:42.592937", -0.340236d, 0.333952d, -0.844012d, -0.245684d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T16:59:06.592937", -0.354773d, 0.329336d, -0.837871d, -0.252281d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T16:59:30.592937", -0.369237d, 0.324612d, -0.831445d, -0.258824d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T16:59:54.592937", -0.3836d, 0.319792d, -0.824743d, -0.265299d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:00:18.592937", -0.397834d, 0.314883d, -0.817777d, -0.271695d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:00:42.592937", -0.411912d, 0.309895d, -0.810561d, -0.278001d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:01:06.592937", -0.42581d, 0.304838d, -0.803111d, -0.284206d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:01:30.592937", -0.439505d, 0.299722d, -0.795442d, -0.290301d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:01:54.592937", -0.452976d, 0.294556d, -0.787571d, -0.296279d);
addSatelliteQ(gps, satelliteQList, "2009-12-11T17:02:18.592937", -0.466207d, 0.28935d, -0.779516d, -0.302131d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T16:58:42.592937", -726361.466d, -5411878.485d, 4637549.599d, -2068.995d, -4500.601d, -5576.736d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T16:59:04.192937", -779538.267d, -5506500.533d, 4515934.894d, -2058.308d, -4369.521d, -5683.906d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T16:59:25.792937", -832615.368d, -5598184.195d, 4392036.13d, -2046.169d, -4236.279d, -5788.201d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T16:59:47.392937", -885556.748d, -5686883.696d, 4265915.971d, -2032.579d, -4100.944d, -5889.568d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:00:08.992937", -938326.32d, -5772554.875d, 4137638.207d, -2017.537d, -3963.59d, -5987.957d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:00:30.592937", -990887.942d, -5855155.21d, 4007267.717d, -2001.046d, -3824.291d, -6083.317d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:00:52.192937", -1043205.448d, -5934643.836d, 3874870.441d, -1983.107d, -3683.122d, -6175.6d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:01:13.792937", -1095242.669d, -6010981.571d, 3740513.34d, -1963.723d, -3540.157d, -6264.76d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:01:35.392937", -1146963.457d, -6084130.93d, 3604264.372d, -1942.899d, -3395.473d, -6350.751d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:01:56.992937", -1198331.706d, -6154056.146d, 3466192.446d, -1920.64d, -3249.148d, -6433.531d);
addSatellitePV(gps, eme2000, itrf, satellitePVList, "2009-12-11T17:02:18.592937", -1249311.381d, -6220723.191d, 3326367.397d, -1896.952d, -3101.26d, -6513.056d);
Rugged rugged = new RuggedBuilder().
setAlgorithm(AlgorithmId.DUVENHAGE).
setDigitalElevationModel(new VolcanicConeElevationUpdater(new GeodeticPoint(FastMath.toRadians(37.58),
FastMath.toRadians(-96.95),
2463.0),
FastMath.toRadians(30.0), 16.0,
FastMath.toRadians(1.0), 1201),
8).
setEllipsoid(EllipsoidId.WGS84, BodyRotatingFrameId.ITRF).
setTimeSpan(absDate, absDate.shiftedBy(60.0), 0.01, 5 / lineSensor.getRate(0)).
setTrajectory(InertialFrameId.EME2000,
satellitePVList, 4, CartesianDerivativesFilter.USE_P,
satelliteQList, 4, AngularDerivativesFilter.USE_R).
addLineSensor(lineSensor).
build();
Vector3D position = lineSensor.getPosition(); // This returns a zero vector since we set the relative position of the sensor w.r.T the satellite to 0.
AbsoluteDate firstLineDate = lineSensor.getDate(0);
Vector3D los = lineSensor.getLos(firstLineDate, 0);
GeodeticPoint upLeftPoint = rugged.directLocation(firstLineDate, position, los);
System.out.format(Locale.US, "upper left point: φ = %8.3f °, λ = %8.3f °, h = %8.3f m%n",
FastMath.toDegrees(upLeftPoint.getLatitude()),
FastMath.toDegrees(upLeftPoint.getLongitude()),
upLeftPoint.getAltitude());
} catch (OrekitException oe) {
System.err.println(oe.getLocalizedMessage());
System.exit(1);
} catch (RuggedException re) {
System.err.println(re.getLocalizedMessage());
System.exit(1);
}
}
private static void addSatellitePV(TimeScale gps, Frame eme2000, Frame itrf,
ArrayList<TimeStampedPVCoordinates> satellitePVList,
String absDate,
double px, double py, double pz, double vx, double vy, double vz)
throws OrekitException {
AbsoluteDate ephemerisDate = new AbsoluteDate(absDate, gps);
Vector3D position = new Vector3D(px, py, pz);
Vector3D velocity = new Vector3D(vx, vy, vz);
PVCoordinates pvITRF = new PVCoordinates(position, velocity);
Transform transform = itrf.getTransformTo(eme2000, ephemerisDate);
Vector3D pEME2000 = transform.transformPosition(pvITRF.getPosition());
Vector3D vEME2000 = transform.transformVector(pvITRF.getVelocity());
satellitePVList.add(new TimeStampedPVCoordinates(ephemerisDate, pEME2000, vEME2000, Vector3D.ZERO));
}
private static void addSatelliteQ(TimeScale gps, ArrayList<TimeStampedAngularCoordinates> satelliteQList, String absDate,
double q0, double q1, double q2, double q3) {
AbsoluteDate attitudeDate = new AbsoluteDate(absDate, gps);
Rotation rotation = new Rotation(q0, q1, q2, q3, true);
TimeStampedAngularCoordinates pair =
new TimeStampedAngularCoordinates(attitudeDate, rotation, Vector3D.ZERO, Vector3D.ZERO);
satelliteQList.add(pair);
}
private static class VolcanicConeElevationUpdater implements TileUpdater {
private GeodeticPoint summit;
private double slope;
private double base;
private double size;
private int n;
public VolcanicConeElevationUpdater(GeodeticPoint summit, double slope, double base,
double size, int n) {
this.summit = summit;
this.slope = slope;
this.base = base;
this.size = size;
this.n = n;
}
public void updateTile(double latitude, double longitude, UpdatableTile tile)
throws RuggedException {
double step = size / (n - 1);
double minLatitude = size * FastMath.floor(latitude / size);
double minLongitude = size * FastMath.floor(longitude / size);
double sinSlope = FastMath.sin(slope);
tile.setGeometry(minLatitude, minLongitude, step, step, n, n);
for (int i = 0; i < n; ++i) {
double cellLatitude = minLatitude + i * step;
for (int j = 0; j < n; ++j) {
double cellLongitude = minLongitude + j * step;
double distance = Constants.WGS84_EARTH_EQUATORIAL_RADIUS *
FastMath.hypot(cellLatitude - summit.getLatitude(),
cellLongitude - summit.getLongitude());
double altitude = FastMath.max(summit.getAltitude() - distance * sinSlope,
base);
tile.setElevation(i, j, altitude);
}
}
}
}
}
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