Examples with AbsoluteDate org.orekit.time.AbsoluteDate used on opensource projects

Example 86 with AbsoluteDate

use of org.orekit.time.AbsoluteDate in project Orekit by CS-SI.

the class EOPHistory method getUT1MinusUTC.

/**
 * Get the UT1-UTC value.
 * <p>The data provided comes from the IERS files. It is smoothed data.</p>
 * @param date date at which the value is desired
 * @param <T> type of the field elements
 * @return UT1-UTC in seconds (0 if date is outside covered range)
 * @since 9.0
 */
public <T extends RealFieldElement<T>> T getUT1MinusUTC(final FieldAbsoluteDate<T> date) {
    // check if there is data for date
    final AbsoluteDate absDate = date.toAbsoluteDate();
    if (!this.hasDataFor(absDate)) {
        // no EOP data available for this date, we use a default 0.0 offset
        return (tidalCorrection == null) ? date.getField().getZero() : tidalCorrection.value(date)[2];
    }
    // we have EOP data -> interpolate offset
    try {
        final FieldDUT1Interpolator<T> interpolator = new FieldDUT1Interpolator<>(date, absDate);
        getNeighbors(absDate).forEach(interpolator);
        T interpolated = interpolator.getInterpolated();
        if (tidalCorrection != null) {
            interpolated = interpolated.add(tidalCorrection.value(date)[2]);
        }
        return interpolated;
    } catch (TimeStampedCacheException tce) {
        // this should not happen because of date check above
        throw new OrekitInternalError(tce);
    }
}

Example 87 with AbsoluteDate

use of org.orekit.time.AbsoluteDate in project Orekit by CS-SI.

the class ConstantThrustManeuver method init.

/**
 * {@inheritDoc}
 */
@Override
public void init(final SpacecraftState s0, final AbsoluteDate t) {
    // set the initial value of firing
    final AbsoluteDate sDate = s0.getDate();
    final boolean isForward = sDate.compareTo(t) < 0;
    final boolean isBetween = startDate.compareTo(sDate) < 0 && endDate.compareTo(sDate) > 0;
    final boolean isOnStart = startDate.compareTo(sDate) == 0;
    final boolean isOnEnd = endDate.compareTo(sDate) == 0;
    firing = isBetween || (isForward && isOnStart) || (!isForward && isOnEnd);
}

Example 88 with AbsoluteDate

use of org.orekit.time.AbsoluteDate in project Orekit by CS-SI.

the class NumericalPropagatorTest method testEphemerisDates.

@Test
public void testEphemerisDates() throws OrekitException {
    // setup
    TimeScale tai = TimeScalesFactory.getTAI();
    AbsoluteDate initialDate = new AbsoluteDate("2015-07-01", tai);
    AbsoluteDate startDate = new AbsoluteDate("2015-07-03", tai).shiftedBy(-0.1);
    AbsoluteDate endDate = new AbsoluteDate("2015-07-04", tai);
    Frame eci = FramesFactory.getGCRF();
    KeplerianOrbit orbit = new KeplerianOrbit(600e3 + Constants.WGS84_EARTH_EQUATORIAL_RADIUS, 0, 0, 0, 0, 0, PositionAngle.TRUE, eci, initialDate, mu);
    OrbitType type = OrbitType.CARTESIAN;
    double[][] tol = NumericalPropagator.tolerances(1e-3, orbit, type);
    NumericalPropagator prop = new NumericalPropagator(new DormandPrince853Integrator(0.1, 500, tol[0], tol[1]));
    prop.setOrbitType(type);
    prop.resetInitialState(new SpacecraftState(new CartesianOrbit(orbit)));
    // action
    prop.setEphemerisMode();
    prop.propagate(startDate, endDate);
    BoundedPropagator ephemeris = prop.getGeneratedEphemeris();
    // verify
    TimeStampedPVCoordinates actualPV = ephemeris.getPVCoordinates(startDate, eci);
    TimeStampedPVCoordinates expectedPV = orbit.getPVCoordinates(startDate, eci);
    MatcherAssert.assertThat(actualPV.getPosition(), OrekitMatchers.vectorCloseTo(expectedPV.getPosition(), 1.0));
    MatcherAssert.assertThat(actualPV.getVelocity(), OrekitMatchers.vectorCloseTo(expectedPV.getVelocity(), 1.0));
    MatcherAssert.assertThat(ephemeris.getMinDate().durationFrom(startDate), OrekitMatchers.closeTo(0, 0));
    MatcherAssert.assertThat(ephemeris.getMaxDate().durationFrom(endDate), OrekitMatchers.closeTo(0, 0));
    // test date
    AbsoluteDate date = endDate.shiftedBy(-0.11);
    Assert.assertEquals(ephemeris.propagate(date).getDate().durationFrom(date), 0, 0);
}

Example 89 with AbsoluteDate

use of org.orekit.time.AbsoluteDate in project Orekit by CS-SI.

the class NumericalPropagatorTest method testParallelismIssue258.

@Test
public void testParallelismIssue258() throws OrekitException, InterruptedException, ExecutionException, FileNotFoundException {
    Utils.setDataRoot("regular-data:atmosphere:potential/grgs-format");
    GravityFieldFactory.addPotentialCoefficientsReader(new GRGSFormatReader("grim4s4_gr", true));
    final double mu = GravityFieldFactory.getNormalizedProvider(2, 2).getMu();
    // Geostationary transfer orbit
    // semi major axis in meters
    final double a = 24396159;
    // eccentricity
    final double e = 0.72831215;
    // inclination
    final double i = FastMath.toRadians(7);
    // perigee argument
    final double omega = FastMath.toRadians(180);
    // right ascension of ascending node
    final double raan = FastMath.toRadians(261);
    // mean anomaly
    final double lM = 0;
    final Frame inertialFrame = FramesFactory.getEME2000();
    final TimeScale utc = TimeScalesFactory.getUTC();
    final AbsoluteDate initialDate = new AbsoluteDate(2003, 1, 1, 00, 00, 00.000, utc);
    final Orbit initialOrbit = new CartesianOrbit(new KeplerianOrbit(a, e, i, omega, raan, lM, PositionAngle.MEAN, inertialFrame, initialDate, mu));
    final SpacecraftState initialState = new SpacecraftState(initialOrbit, 1000);
    // initialize the testing points
    final List<SpacecraftState> states = new ArrayList<SpacecraftState>();
    final NumericalPropagator propagator = createPropagator(initialState, OrbitType.CARTESIAN, PositionAngle.TRUE);
    final double samplingStep = 10000.0;
    propagator.setMasterMode(samplingStep, (state, isLast) -> states.add(state));
    propagator.propagate(initialDate.shiftedBy(5 * samplingStep));
    // compute reference errors, using serial computation in a for loop
    final double[][] referenceErrors = new double[states.size() - 1][];
    for (int startIndex = 0; startIndex < states.size() - 1; ++startIndex) {
        referenceErrors[startIndex] = recomputeFollowing(startIndex, states);
    }
    final Consumer<SpacecraftState> checker = point -> {
        try {
            final int startIndex = states.indexOf(point);
            double[] errors = recomputeFollowing(startIndex, states);
            for (int k = 0; k < errors.length; ++k) {
                Assert.assertEquals(startIndex + " to " + (startIndex + k + 1), referenceErrors[startIndex][k], errors[k], 1.0e-9);
            }
        } catch (OrekitException oe) {
            Assert.fail(oe.getLocalizedMessage());
        }
    };
    // serial propagation using Stream
    states.stream().forEach(checker);
    // parallel propagation using parallelStream
    states.parallelStream().forEach(checker);
}

Example 90 with AbsoluteDate

use of org.orekit.time.AbsoluteDate in project Orekit by CS-SI.

the class NumericalPropagatorTest method createEllipticOrbit.

private CartesianOrbit createEllipticOrbit() throws OrekitException {
    final AbsoluteDate date = new AbsoluteDate("2003-05-01T00:00:20.000", TimeScalesFactory.getUTC());
    final Vector3D position = new Vector3D(6896874.444705, 1956581.072644, -147476.245054);
    final Vector3D velocity = new Vector3D(166.816407662, -1106.783301861, -7372.745712770);
    final TimeStampedPVCoordinates pv = new TimeStampedPVCoordinates(date, position, velocity);
    final Frame frame = FramesFactory.getEME2000();
    final double mu = Constants.EIGEN5C_EARTH_MU;
    return new CartesianOrbit(pv, frame, mu);
}