FieldCircularOrbit (ORbit Extrapolation KIT 10.0 API)

java.lang.Object
- org.orekit.orbits.FieldOrbit<T>
- - org.orekit.orbits.FieldCircularOrbit<T>

All Implemented Interfaces:

FieldTimeInterpolable<FieldOrbit<T>,T>, FieldTimeShiftable<FieldOrbit<T>,T>, FieldTimeStamped<T>, FieldPVCoordinatesProvider<T>
```
public class FieldCircularOrbit<T extends RealFieldElement<T>>
extends FieldOrbit<T>
```
This class handles circular orbital parameters.
The parameters used internally are the circular elements which can be related to Keplerian elements as follows:
- a
- e_x = e cos(ω)
- e_y = e sin(ω)
- i
- Ω
- α_v = v + ω
where Ω stands for the Right Ascension of the Ascending Node and α_v stands for the true latitude argument
The conversion equations from and to Keplerian elements given above hold only when both sides are unambiguously defined, i.e. when orbit is neither equatorial nor circular. When orbit is circular (but not equatorial), the circular parameters are still unambiguously defined whereas some Keplerian elements (more precisely ω and Ω) become ambiguous. When orbit is equatorial, neither the Keplerian nor the circular parameters can be defined unambiguously. equinoctial orbits is the recommended way to represent orbits.

The instance CircularOrbit is guaranteed to be immutable.
Since:

9.0

Author:

Luc Maisonobe, Fabien Maussion, Véronique Pommier-Maurussane

See Also:

Orbit, KeplerianOrbit, CartesianOrbit, EquinoctialOrbit

Constructor Summary

Constructors
Constructor and Description
`FieldCircularOrbit(FieldOrbit<T> op)` Constructor from any kind of orbital parameters.
`FieldCircularOrbit(FieldPVCoordinates<T> PVCoordinates, Frame frame, FieldAbsoluteDate<T> date, T mu)` Constructor from Cartesian parameters.
`FieldCircularOrbit(TimeStampedFieldPVCoordinates<T> pvCoordinates, Frame frame, T mu)` Constructor from Cartesian parameters.
`FieldCircularOrbit(T a, T ex, T ey, T i, T raan, T alpha, PositionAngle type, Frame frame, FieldAbsoluteDate<T> date, T mu)` Creates a new instance.
`FieldCircularOrbit(T a, T ex, T ey, T i, T raan, T alpha, T aDot, T exDot, T eyDot, T iDot, T raanDot, T alphaDot, PositionAngle type, Frame frame, FieldAbsoluteDate<T> date, T mu)` Creates a new instance.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addKeplerContribution(PositionAngle type, T gm, T[] pDot)` Add the contribution of the Keplerian motion to parameters derivatives
`protected T[][]`	`computeJacobianEccentricWrtCartesian()` Compute the Jacobian of the orbital parameters with eccentric angle with respect to the Cartesian parameters.
`protected T[][]`	`computeJacobianMeanWrtCartesian()` Compute the Jacobian of the orbital parameters with mean angle with respect to the Cartesian parameters.
`protected T[][]`	`computeJacobianTrueWrtCartesian()` Compute the Jacobian of the orbital parameters with true angle with respect to the Cartesian parameters.
`static <T extends RealFieldElement<T>> T`	`eccentricToMean(T alphaE, T ex, T ey)` Computes the mean latitude argument from the eccentric latitude argument.
`static <T extends RealFieldElement<T>> T`	`eccentricToTrue(T alphaE, T ex, T ey)` Computes the true latitude argument from the eccentric latitude argument.
`T`	`getA()` Get the semi-major axis.
`T`	`getADot()` Get the semi-major axis derivative.
`T`	`getAlpha(PositionAngle type)` Get the latitude argument.
`T`	`getAlphaDot(PositionAngle type)` Get the latitude argument derivative.
`T`	`getAlphaE()` Get the eccentric latitude argument.
`T`	`getAlphaEDot()` Get the eccentric latitude argument derivative.
`T`	`getAlphaM()` Get the mean latitude argument.
`T`	`getAlphaMDot()` Get the mean latitude argument derivative.
`T`	`getAlphaV()` Get the true latitude argument.
`T`	`getAlphaVDot()` Get the true latitude argument derivative.
`T`	`getCircularEx()` Get the first component of the circular eccentricity vector.
`T`	`getCircularExDot()` Get the first component of the circular eccentricity vector derivative.
`T`	`getCircularEy()` Get the second component of the circular eccentricity vector.
`T`	`getCircularEyDot()` Get the second component of the circular eccentricity vector derivative.
`T`	`getE()` Get the eccentricity.
`T`	`getEDot()` Get the eccentricity derivative.
`T`	`getEquinoctialEx()` Get the first component of the equinoctial eccentricity vector.
`T`	`getEquinoctialExDot()` Get the first component of the equinoctial eccentricity vector.
`T`	`getEquinoctialEy()` Get the second component of the equinoctial eccentricity vector.
`T`	`getEquinoctialEyDot()` Get the second component of the equinoctial eccentricity vector.
`T`	`getHx()` Get the first component of the inclination vector.
`T`	`getHxDot()` Get the first component of the inclination vector derivative.
`T`	`getHy()` Get the second component of the inclination vector.
`T`	`getHyDot()` Get the second component of the inclination vector derivative.
`T`	`getI()` Get the inclination.
`T`	`getIDot()` Get the inclination derivative.
`T`	`getLE()` Get the eccentric longitude argument.
`T`	`getLEDot()` Get the eccentric longitude argument derivative.
`T`	`getLM()` Get the mean longitude argument.
`T`	`getLMDot()` Get the mean longitude argument derivative.
`T`	`getLv()` Get the true longitude argument.
`T`	`getLvDot()` Get the true longitude argument derivative.
`T`	`getRightAscensionOfAscendingNode()` Get the right ascension of the ascending node.
`T`	`getRightAscensionOfAscendingNodeDot()` Get the right ascension of the ascending node derivative.
`OrbitType`	`getType()` Get the orbit type.
`boolean`	`hasDerivatives()` Check if orbit includes derivatives.
`protected TimeStampedFieldPVCoordinates<T>`	`initPVCoordinates()` Compute the position/velocity coordinates from the canonical parameters.
`FieldCircularOrbit<T>`	`interpolate(FieldAbsoluteDate<T> date, Stream<FieldOrbit<T>> sample)` Get an interpolated instance.
`static <T extends RealFieldElement<T>> T`	`meanToEccentric(T alphaM, T ex, T ey)` Computes the eccentric latitude argument from the mean latitude argument.
`static <T extends RealFieldElement<T>> T`	`normalizeAngle(T a, T center)` Normalize an angle in a 2π wide interval around a center value.
`FieldCircularOrbit<T>`	`shiftedBy(double dt)` Get a time-shifted instance.
`FieldCircularOrbit<T>`	`shiftedBy(T dt)` Get a time-shifted orbit.
`CircularOrbit`	`toOrbit()` Transforms the FieldOrbit instance into an Orbit instance.
`String`	`toString()` Returns a string representation of this Orbit object.
`static <T extends RealFieldElement<T>> T`	`trueToEccentric(T alphaV, T ex, T ey)` Computes the eccentric latitude argument from the true latitude argument.

Methods inherited from class org.orekit.orbits.FieldOrbit
fillHalfRow, fillHalfRow, fillHalfRow, fillHalfRow, fillHalfRow, fillHalfRow, getDate, getFrame, getJacobianWrtCartesian, getJacobianWrtParameters, getKeplerianMeanMotion, getKeplerianPeriod, getMu, getPVCoordinates, getPVCoordinates, getPVCoordinates, hasNonKeplerianAcceleration

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.orekit.time.FieldTimeInterpolable
interpolate

- Constructor Detail
  - FieldCircularOrbit
```
public FieldCircularOrbit(T a,
                          T ex,
                          T ey,
                          T i,
                          T raan,
                          T alpha,
                          PositionAngle type,
                          Frame frame,
                          FieldAbsoluteDate<T> date,
                          T mu)
                   throws IllegalArgumentException
```
    Creates a new instance.
    
    Parameters:
    
    a - semi-major axis (m)
    
    ex - e cos(ω), first component of circular eccentricity vector
    
    ey - e sin(ω), second component of circular eccentricity vector
    
    i - inclination (rad)
    
    raan - right ascension of ascending node (Ω, rad)
    
    alpha - an + ω, mean, eccentric or true latitude argument (rad)
    
    type - type of latitude argument
    
    frame - the frame in which are defined the parameters (must be a pseudo-inertial frame)
    
    date - date of the orbital parameters
    
    mu - central attraction coefficient (m³/s²)
    
    Throws:
    
    IllegalArgumentException - if eccentricity is equal to 1 or larger or if frame is not a pseudo-inertial frame
  - FieldCircularOrbit
```
public FieldCircularOrbit(T a,
                          T ex,
                          T ey,
                          T i,
                          T raan,
                          T alpha,
                          T aDot,
                          T exDot,
                          T eyDot,
                          T iDot,
                          T raanDot,
                          T alphaDot,
                          PositionAngle type,
                          Frame frame,
                          FieldAbsoluteDate<T> date,
                          T mu)
                   throws IllegalArgumentException
```
    Creates a new instance.
    
    Parameters:
    
    a - semi-major axis (m)
    
    ex - e cos(ω), first component of circular eccentricity vector
    
    ey - e sin(ω), second component of circular eccentricity vector
    
    i - inclination (rad)
    
    raan - right ascension of ascending node (Ω, rad)
    
    alpha - an + ω, mean, eccentric or true latitude argument (rad)
    
    aDot - semi-major axis derivative (m/s)
    
    exDot - d(e cos(ω))/dt, first component of circular eccentricity vector derivative
    
    eyDot - d(e sin(ω))/dt, second component of circular eccentricity vector derivative
    
    iDot - inclination derivative(rad/s)
    
    raanDot - right ascension of ascending node derivative (rad/s)
    
    alphaDot - d(an + ω), mean, eccentric or true latitude argument derivative (rad/s)
    
    type - type of latitude argument
    
    frame - the frame in which are defined the parameters (must be a pseudo-inertial frame)
    
    date - date of the orbital parameters
    
    mu - central attraction coefficient (m³/s²)
    
    Throws:
    
    IllegalArgumentException - if eccentricity is equal to 1 or larger or if frame is not a pseudo-inertial frame
  - FieldCircularOrbit
```
public FieldCircularOrbit(TimeStampedFieldPVCoordinates<T> pvCoordinates,
                          Frame frame,
                          T mu)
                   throws IllegalArgumentException
```
    Constructor from Cartesian parameters.
    The acceleration provided in FieldPVCoordinates is accessible using FieldOrbit.getPVCoordinates() and FieldOrbit.getPVCoordinates(Frame). All other methods use mu and the position to compute the acceleration, including shiftedBy(RealFieldElement) and FieldOrbit.getPVCoordinates(FieldAbsoluteDate, Frame).
    
    Parameters:
    
    pvCoordinates - the FieldPVCoordinates in inertial frame
    
    frame - the frame in which are defined the FieldPVCoordinates (must be a pseudo-inertial frame)
    
    mu - central attraction coefficient (m³/s²)
    
    Throws:
    
    IllegalArgumentException - if frame is not a pseudo-inertial frame
  - FieldCircularOrbit
```
public FieldCircularOrbit(FieldPVCoordinates<T> PVCoordinates,
                          Frame frame,
                          FieldAbsoluteDate<T> date,
                          T mu)
                   throws IllegalArgumentException
```
    Constructor from Cartesian parameters.
    The acceleration provided in FieldPVCoordinates is accessible using FieldOrbit.getPVCoordinates() and FieldOrbit.getPVCoordinates(Frame). All other methods use mu and the position to compute the acceleration, including shiftedBy(RealFieldElement) and FieldOrbit.getPVCoordinates(FieldAbsoluteDate, Frame).
    
    Parameters:
    
    PVCoordinates - the FieldPVCoordinates in inertial frame
    
    frame - the frame in which are defined the FieldPVCoordinates (must be a pseudo-inertial frame)
    
    date - date of the orbital parameters
    
    mu - central attraction coefficient (m³/s²)
    
    Throws:
    
    IllegalArgumentException - if frame is not a pseudo-inertial frame
  - FieldCircularOrbit
```
public FieldCircularOrbit(FieldOrbit<T> op)
```
    Constructor from any kind of orbital parameters.
    
    Parameters:
    
    op - orbital parameters to copy
- Method Detail
  - getType
```
public OrbitType getType()
```
    Get the orbit type.
    
    Specified by:
    
    getType in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    orbit type
  - getA
```
public T getA()
```
    Get the semi-major axis.
    Note that the semi-major axis is considered negative for hyperbolic orbits.
    
    Specified by:
    
    getA in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    semi-major axis (m)
  - getADot
```
public T getADot()
```
    Get the semi-major axis derivative.
    Note that the semi-major axis is considered negative for hyperbolic orbits.
    
    If the orbit was created without derivatives, the value returned is null.
    
    Specified by:
    
    getADot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    semi-major axis derivative (m/s)
  - getEquinoctialEx
```
public T getEquinoctialEx()
```
    Get the first component of the equinoctial eccentricity vector.
    
    Specified by:
    
    getEquinoctialEx in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    first component of the equinoctial eccentricity vector
  - getEquinoctialExDot
```
public T getEquinoctialExDot()
```
    Get the first component of the equinoctial eccentricity vector.
    If the orbit was created without derivatives, the value returned is null.
    
    Specified by:
    
    getEquinoctialExDot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    first component of the equinoctial eccentricity vector
  - getEquinoctialEy
```
public T getEquinoctialEy()
```
    Get the second component of the equinoctial eccentricity vector.
    
    Specified by:
    
    getEquinoctialEy in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    second component of the equinoctial eccentricity vector
  - getEquinoctialEyDot
```
public T getEquinoctialEyDot()
```
    Get the second component of the equinoctial eccentricity vector.
    If the orbit was created without derivatives, the value returned is null.
    
    Specified by:
    
    getEquinoctialEyDot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    second component of the equinoctial eccentricity vector
  - getCircularEx
```
public T getCircularEx()
```
    Get the first component of the circular eccentricity vector.
    
    Returns:
    
    ex = e cos(ω), first component of the circular eccentricity vector
  - getCircularExDot
```
public T getCircularExDot()
```
    Get the first component of the circular eccentricity vector derivative.
    
    Returns:
    
    d(ex)/dt = d(e cos(ω))/dt, first component of the circular eccentricity vector derivative
  - getCircularEy
```
public T getCircularEy()
```
    Get the second component of the circular eccentricity vector.
    
    Returns:
    
    ey = e sin(ω), second component of the circular eccentricity vector
  - getCircularEyDot
```
public T getCircularEyDot()
```
    Get the second component of the circular eccentricity vector derivative.
    
    Returns:
    
    d(ey)/dt = d(e sin(ω))/dt, second component of the circular eccentricity vector derivative
  - getHx
```
public T getHx()
```
    Get the first component of the inclination vector.
    
    Specified by:
    
    getHx in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    first component of the inclination vector
  - getHxDot
```
public T getHxDot()
```
    Get the first component of the inclination vector derivative.
    If the orbit was created without derivatives, the value returned is null.
    
    Specified by:
    
    getHxDot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    first component of the inclination vector derivative
  - getHy
```
public T getHy()
```
    Get the second component of the inclination vector.
    
    Specified by:
    
    getHy in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    second component of the inclination vector
  - getHyDot
```
public T getHyDot()
```
    Get the second component of the inclination vector derivative.
    
    Specified by:
    
    getHyDot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    second component of the inclination vector derivative
  - getAlphaV
```
public T getAlphaV()
```
    Get the true latitude argument.
    
    Returns:
    
    v + ω true latitude argument (rad)
  - getAlphaVDot
```
public T getAlphaVDot()
```
    Get the true latitude argument derivative.
    
    Returns:
    
    d(v + ω)/dt true latitude argument derivative (rad/s)
  - getAlphaE
```
public T getAlphaE()
```
    Get the eccentric latitude argument.
    
    Returns:
    
    E + ω eccentric latitude argument (rad)
  - getAlphaEDot
```
public T getAlphaEDot()
```
    Get the eccentric latitude argument derivative.
    
    Returns:
    
    d(E + ω)/dt eccentric latitude argument derivative (rad/s)
  - getAlphaM
```
public T getAlphaM()
```
    Get the mean latitude argument.
    
    Returns:
    
    M + ω mean latitude argument (rad)
  - getAlphaMDot
```
public T getAlphaMDot()
```
    Get the mean latitude argument derivative.
    
    Returns:
    
    d(M + ω)/dt mean latitude argument derivative (rad/s)
  - getAlpha
```
public T getAlpha(PositionAngle type)
```
    Get the latitude argument.
    
    Parameters:
    
    type - type of the angle
    
    Returns:
    
    latitude argument (rad)
  - getAlphaDot
```
public T getAlphaDot(PositionAngle type)
```
    Get the latitude argument derivative.
    
    Parameters:
    
    type - type of the angle
    
    Returns:
    
    latitude argument derivative (rad/s)
  - eccentricToTrue
```
public static <T extends RealFieldElement<T>> T eccentricToTrue(T alphaE,
                                                                T ex,
                                                                T ey)
```
    Computes the true latitude argument from the eccentric latitude argument.
    
    Type Parameters:
    
    T - Type of the field elements
    
    Parameters:
    
    alphaE - = E + ω eccentric latitude argument (rad)
    
    ex - e cos(ω), first component of circular eccentricity vector
    
    ey - e sin(ω), second component of circular eccentricity vector
    
    Returns:
    
    the true latitude argument.
  - trueToEccentric
```
public static <T extends RealFieldElement<T>> T trueToEccentric(T alphaV,
                                                                T ex,
                                                                T ey)
```
    Computes the eccentric latitude argument from the true latitude argument.
    
    Type Parameters:
    
    T - Type of the field elements
    
    Parameters:
    
    alphaV - = v + ω true latitude argument (rad)
    
    ex - e cos(ω), first component of circular eccentricity vector
    
    ey - e sin(ω), second component of circular eccentricity vector
    
    Returns:
    
    the eccentric latitude argument.
  - meanToEccentric
```
public static <T extends RealFieldElement<T>> T meanToEccentric(T alphaM,
                                                                T ex,
                                                                T ey)
```
    Computes the eccentric latitude argument from the mean latitude argument.
    
    Type Parameters:
    
    T - Type of the field elements
    
    Parameters:
    
    alphaM - = M + ω mean latitude argument (rad)
    
    ex - e cos(ω), first component of circular eccentricity vector
    
    ey - e sin(ω), second component of circular eccentricity vector
    
    Returns:
    
    the eccentric latitude argument.
  - eccentricToMean
```
public static <T extends RealFieldElement<T>> T eccentricToMean(T alphaE,
                                                                T ex,
                                                                T ey)
```
    Computes the mean latitude argument from the eccentric latitude argument.
    
    Type Parameters:
    
    T - Type of the field elements
    
    Parameters:
    
    alphaE - = E + ω eccentric latitude argument (rad)
    
    ex - e cos(ω), first component of circular eccentricity vector
    
    ey - e sin(ω), second component of circular eccentricity vector
    
    Returns:
    
    the mean latitude argument.
  - getE
```
public T getE()
```
    Get the eccentricity.
    
    Specified by:
    
    getE in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    eccentricity
  - getEDot
```
public T getEDot()
```
    Get the eccentricity derivative.
    If the orbit was created without derivatives, the value returned is null.
    
    Specified by:
    
    getEDot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    eccentricity derivative
  - getI
```
public T getI()
```
    Get the inclination.
    If the orbit was created without derivatives, the value returned is null.
    
    Specified by:
    
    getI in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    inclination (rad)
  - getIDot
```
public T getIDot()
```
    Get the inclination derivative.
    
    Specified by:
    
    getIDot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    inclination derivative (rad/s)
  - getRightAscensionOfAscendingNode
```
public T getRightAscensionOfAscendingNode()
```
    Get the right ascension of the ascending node.
    
    Returns:
    
    right ascension of the ascending node (rad)
  - getRightAscensionOfAscendingNodeDot
```
public T getRightAscensionOfAscendingNodeDot()
```
    Get the right ascension of the ascending node derivative.
    
    Returns:
    
    right ascension of the ascending node derivative (rad/s)
  - getLv
```
public T getLv()
```
    Get the true longitude argument.
    
    Specified by:
    
    getLv in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    v + ω + Ω true longitude argument (rad)
  - getLvDot
```
public T getLvDot()
```
    Get the true longitude argument derivative.
    If the orbit was created without derivatives, the value returned is null.
    
    Specified by:
    
    getLvDot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    d(v + ω + Ω)/dt true longitude argument derivative (rad/s)
  - getLE
```
public T getLE()
```
    Get the eccentric longitude argument.
    
    Specified by:
    
    getLE in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    E + ω + Ω eccentric longitude argument (rad)
  - getLEDot
```
public T getLEDot()
```
    Get the eccentric longitude argument derivative.
    If the orbit was created without derivatives, the value returned is null.
    
    Specified by:
    
    getLEDot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    d(E + ω + Ω)/dt eccentric longitude argument derivative (rad/s)
  - getLM
```
public T getLM()
```
    Get the mean longitude argument.
    
    Specified by:
    
    getLM in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    M + ω + Ω mean longitude argument (rad)
  - getLMDot
```
public T getLMDot()
```
    Get the mean longitude argument derivative.
    If the orbit was created without derivatives, the value returned is null.
    
    Specified by:
    
    getLMDot in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    d(M + ω + Ω)/dt mean longitude argument derivative (rad/s)
  - hasDerivatives
```
public boolean hasDerivatives()
```
    Check if orbit includes derivatives.
    
    Specified by:
    
    hasDerivatives in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    true if orbit includes derivatives
    
    See Also:
    
    FieldOrbit.getADot(), FieldOrbit.getEquinoctialExDot(), FieldOrbit.getEquinoctialEyDot(), FieldOrbit.getHxDot(), FieldOrbit.getHyDot(), FieldOrbit.getLEDot(), FieldOrbit.getLvDot(), FieldOrbit.getLMDot(), FieldOrbit.getEDot(), FieldOrbit.getIDot()
  - initPVCoordinates
```
protected TimeStampedFieldPVCoordinates<T> initPVCoordinates()
```
    Compute the position/velocity coordinates from the canonical parameters.
    
    Specified by:
    
    initPVCoordinates in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    computed position/velocity coordinates
  - shiftedBy
```
public FieldCircularOrbit<T> shiftedBy(double dt)
```
    Get a time-shifted instance.
    
    Parameters:
    
    dt - time shift in seconds
    
    Returns:
    
    a new instance, shifted with respect to instance (which is not changed)
  - shiftedBy
```
public FieldCircularOrbit<T> shiftedBy(T dt)
```
    Get a time-shifted orbit.
    The orbit can be slightly shifted to close dates. This shift is based on a simple Keplerian model. It is not intended as a replacement for proper orbit and attitude propagation but should be sufficient for small time shifts or coarse accuracy.
    
    Specified by:
    
    shiftedBy in interface FieldTimeShiftable<FieldOrbit<T extends RealFieldElement<T>>,T extends RealFieldElement<T>>
    
    Specified by:
    
    shiftedBy in class FieldOrbit<T extends RealFieldElement<T>>
    
    Parameters:
    
    dt - time shift in seconds
    
    Returns:
    
    a new orbit, shifted with respect to the instance (which is immutable)
  - interpolate
```
public FieldCircularOrbit<T> interpolate(FieldAbsoluteDate<T> date,
                                         Stream<FieldOrbit<T>> sample)
```
    Get an interpolated instance.
    Note that the state of the current instance may not be used in the interpolation process, only its type and non interpolable fields are used (for example central attraction coefficient or frame when interpolating orbits). The interpolable fields taken into account are taken only from the states of the sample points. So if the state of the instance must be used, the instance should be included in the sample points.
    
    Note that this method is designed for small samples only (say up to about 10-20 points) so it can be implemented using polynomial interpolation (typically Hermite interpolation). Using too much points may induce Runge's phenomenon and numerical problems (including NaN appearing).
    
    The interpolated instance is created by polynomial Hermite interpolation on circular elements, without derivatives (which means the interpolation falls back to Lagrange interpolation only).
    
    As this implementation of interpolation is polynomial, it should be used only with small samples (about 10-20 points) in order to avoid Runge's phenomenon and numerical problems (including NaN appearing).
    
    If orbit interpolation on large samples is needed, using the Ephemeris class is a better way than using this low-level interpolation. The Ephemeris class automatically handles selection of a neighboring sub-sample with a predefined number of point from a large global sample in a thread-safe way.
    
    Parameters:
    
    date - interpolation date
    
    sample - sample points on which interpolation should be done
    
    Returns:
    
    a new instance, interpolated at specified date
  - computeJacobianMeanWrtCartesian
```
protected T[][] computeJacobianMeanWrtCartesian()
```
    Compute the Jacobian of the orbital parameters with mean angle with respect to the Cartesian parameters.
    Element jacobian[i][j] is the derivative of parameter i of the orbit with respect to Cartesian coordinate j. This means each row correspond to one orbital parameter whereas columns 0 to 5 correspond to the Cartesian coordinates x, y, z, xDot, yDot and zDot.
    
    Specified by:
    
    computeJacobianMeanWrtCartesian in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    6x6 Jacobian matrix
    
    See Also:
    
    FieldOrbit.computeJacobianEccentricWrtCartesian(), FieldOrbit.computeJacobianTrueWrtCartesian()
  - computeJacobianEccentricWrtCartesian
```
protected T[][] computeJacobianEccentricWrtCartesian()
```
    Compute the Jacobian of the orbital parameters with eccentric angle with respect to the Cartesian parameters.
    Element jacobian[i][j] is the derivative of parameter i of the orbit with respect to Cartesian coordinate j. This means each row correspond to one orbital parameter whereas columns 0 to 5 correspond to the Cartesian coordinates x, y, z, xDot, yDot and zDot.
    
    Specified by:
    
    computeJacobianEccentricWrtCartesian in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    6x6 Jacobian matrix
    
    See Also:
    
    FieldOrbit.computeJacobianMeanWrtCartesian(), FieldOrbit.computeJacobianTrueWrtCartesian()
  - computeJacobianTrueWrtCartesian
```
protected T[][] computeJacobianTrueWrtCartesian()
```
    Compute the Jacobian of the orbital parameters with true angle with respect to the Cartesian parameters.
    Element jacobian[i][j] is the derivative of parameter i of the orbit with respect to Cartesian coordinate j. This means each row correspond to one orbital parameter whereas columns 0 to 5 correspond to the Cartesian coordinates x, y, z, xDot, yDot and zDot.
    
    Specified by:
    
    computeJacobianTrueWrtCartesian in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    6x6 Jacobian matrix
    
    See Also:
    
    FieldOrbit.computeJacobianMeanWrtCartesian(), FieldOrbit.computeJacobianEccentricWrtCartesian()
  - addKeplerContribution
```
public void addKeplerContribution(PositionAngle type,
                                  T gm,
                                  T[] pDot)
```
    Add the contribution of the Keplerian motion to parameters derivatives
    This method is used by integration-based propagators to evaluate the part of Keplerian motion to evolution of the orbital state.
    
    Specified by:
    
    addKeplerContribution in class FieldOrbit<T extends RealFieldElement<T>>
    
    Parameters:
    
    type - type of the position angle in the state
    
    gm - attraction coefficient to use
    
    pDot - array containing orbital state derivatives to update (the Keplerian part must be added to the array components, as the array may already contain some non-zero elements corresponding to non-Keplerian parts)
  - toString
```
public String toString()
```
    Returns a string representation of this Orbit object.
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    a string representation of this object
  - normalizeAngle
```
public static <T extends RealFieldElement<T>> T normalizeAngle(T a,
                                                               T center)
```
    Normalize an angle in a 2π wide interval around a center value.
    This method has three main uses:
    - normalize an angle between 0 and 2π:
      a = MathUtils.normalizeAngle(a, FastMath.PI);
    - normalize an angle between -π and +π
      a = MathUtils.normalizeAngle(a, 0.0);
    - compute the angle between two defining angular positions:
      angle = MathUtils.normalizeAngle(end, start) - start;
    Note that due to numerical accuracy and since π cannot be represented exactly, the result interval is closed, it cannot be half-closed as would be more satisfactory in a purely mathematical view.
    Type Parameters:
    
    T - the type of the field elements
    
    Parameters:
    
    a - angle to normalize
    
    center - center of the desired 2π interval for the result
    
    Returns:
    
    a-2kπ with integer k and center-π <= a-2kπ <= center+π
  - toOrbit
```
public CircularOrbit toOrbit()
```
    Description copied from class: FieldOrbit
    
    Transforms the FieldOrbit instance into an Orbit instance.
    
    Specified by:
    
    toOrbit in class FieldOrbit<T extends RealFieldElement<T>>
    
    Returns:
    
    Orbit instance with same properties

Class FieldCircularOrbit<T extends RealFieldElement<T>>

Constructor Summary

Method Summary

Methods inherited from class org.orekit.orbits.FieldOrbit

Methods inherited from class java.lang.Object

Methods inherited from interface org.orekit.time.FieldTimeInterpolable

Constructor Detail

FieldCircularOrbit

FieldCircularOrbit

FieldCircularOrbit

FieldCircularOrbit

FieldCircularOrbit

Method Detail

getType

getA

getADot

getEquinoctialEx

getEquinoctialExDot

getEquinoctialEy

getEquinoctialEyDot

getCircularEx

getCircularExDot

getCircularEy

getCircularEyDot

getHx

getHxDot

getHy

getHyDot

getAlphaV

getAlphaVDot

getAlphaE

getAlphaEDot

getAlphaM

getAlphaMDot

getAlpha

getAlphaDot

eccentricToTrue

trueToEccentric

meanToEccentric

eccentricToMean

getE

getEDot

getI

getIDot

getRightAscensionOfAscendingNode

getRightAscensionOfAscendingNodeDot

getLv

getLvDot

getLE

getLEDot

getLM

getLMDot

hasDerivatives

initPVCoordinates

shiftedBy

shiftedBy

interpolate

computeJacobianMeanWrtCartesian

computeJacobianEccentricWrtCartesian

computeJacobianTrueWrtCartesian

addKeplerContribution

toString

normalizeAngle

toOrbit