org.orekit.propagation.semianalytical.dsst.utilities.hansen

Class FieldHansenZonalLinear<T extends CalculusFieldElement<T>>

java.lang.Object

org.orekit.propagation.semianalytical.dsst.utilities.hansen.FieldHansenZonalLinear<T>

public class FieldHansenZonalLinear<T extends CalculusFieldElement<T>>
extends Object

Hansen coefficients K(t,n,s) for t=0 and n < 0.

Implements Collins 4-242 or echivalently, Danielson 2.7.3-(6) for Hansen Coefficients and Collins 4-245 or Danielson 3.1-(7) for derivatives. The recursions are transformed into composition of linear transformations to obtain the associated polynomials for coefficients and their derivatives - see Petre's paper

Author:

Petre Bazavan, Lucian Barbulescu, Bryan Cazabonne

Constructor Summary

Constructors

Constructor and Description
FieldHansenZonalLinear(int nMax, int s, Field<T> field) Constructor.

Method Summary

Modifier and Type	Method and Description
void	computeInitValues(T chi) Compute the roots for the Hansen coefficients and their derivatives.
T	getDerivative(int mnm1, T chi) Get the dK₀-n-1,s / dΧ coefficient derivative.
T	getValue(int mnm1, T chi) Get the K₀-n-1,s coefficient value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FieldHansenZonalLinear

public FieldHansenZonalLinear(int nMax,
                              int s,
                              Field<T> field)

Constructor.

Parameters:

nMax - the maximum (absolute) value of n coefficient

s - s coefficient

field - field used by default

Method Detail

computeInitValues

public void computeInitValues(T chi)

Compute the roots for the Hansen coefficients and their derivatives.

Parameters:

chi - 1 / sqrt(1 - e²)

getValue

public T getValue(int mnm1,
                  T chi)

Get the K₀^-n-1,s coefficient value.

The s value is given in the class constructor

Parameters:

mnm1 - (-n-1) coefficient

chi - The value of χ

Returns:

K₀^-n-1,s

getDerivative

public T getDerivative(int mnm1,
                       T chi)

Get the dK₀^-n-1,s / dΧ coefficient derivative.

The s value is given in the class constructor.

Parameters:

mnm1 - (-n-1) coefficient

chi - The value of χ

Returns:

dK₀^-n-1,s / dΧ