org.orekit.frames

Class EOPHistory

java.lang.Object

org.orekit.frames.EOPHistory

All Implemented Interfaces:

Serializable

public class EOPHistory
extends Object
implements Serializable

This class loads any kind of Earth Orientation Parameter data throughout a large time range.

Author:

Pascal Parraud

See Also:

Serialized Form

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	EOPHistory(IERSConventions conventions, Collection<EOPEntry> data, boolean simpleEOP) Simple constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	checkEOPContinuity(double maxGap) Check Earth orientation parameters continuity.
IERSConventions	getConventions() Get the IERS conventions to which these EOP apply.
AbsoluteDate	getEndDate() Get the date of the last available Earth Orientation Parameters.
double[]	getEquinoxNutationCorrection(AbsoluteDate date) Get the correction to the nutation parameters for equinox-based paradigm.
double	getLOD(AbsoluteDate date) Get the LoD (Length of Day) value.
protected List<EOPEntry>	getNeighbors(AbsoluteDate central) Get the entries surrounding a central date.
double[]	getNonRotatinOriginNutationCorrection(AbsoluteDate date) Get the correction to the nutation parameters for Non-Rotating Origin paradigm.
PoleCorrection	getPoleCorrection(AbsoluteDate date) Get the pole IERS Reference Pole correction.
AbsoluteDate	getStartDate() Get the date of the first available Earth Orientation Parameters.
double	getUT1MinusUTC(AbsoluteDate date) Get the UT1-UTC value.
protected boolean	hasDataFor(AbsoluteDate date) Check if the cache has data for the given date using getStartDate() and getEndDate().

Methods inherited from class java.lang.Object

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

Constructor Detail

EOPHistory

protected EOPHistory(IERSConventions conventions,
          Collection<EOPEntry> data,
          boolean simpleEOP)
              throws OrekitException

Simple constructor.

Parameters:

conventions - IERS conventions to which EOP refers

data - the EOP data to use

simpleEOP - if true, tidal effects are ignored when interpolating EOP

Throws:

OrekitException - if tidal correction model cannot be loaded

Method Detail

getConventions

public IERSConventions getConventions()

Get the IERS conventions to which these EOP apply.

Returns:

IERS conventions to which these EOP apply

getStartDate

public AbsoluteDate getStartDate()

Get the date of the first available Earth Orientation Parameters.

Returns:

the start date of the available data

getEndDate

public AbsoluteDate getEndDate()

Get the date of the last available Earth Orientation Parameters.

Returns:

the end date of the available data

getUT1MinusUTC

public double getUT1MinusUTC(AbsoluteDate date)

Get the UT1-UTC value.

The data provided comes from the IERS files. It is smoothed data.

Parameters:

date - date at which the value is desired

Returns:

UT1-UTC in seconds (0 if date is outside covered range)

getNeighbors

protected List<EOPEntry> getNeighbors(AbsoluteDate central)
                               throws TimeStampedCacheException

Get the entries surrounding a central date.

See hasDataFor(AbsoluteDate) to determine if the cache has data for central without throwing an exception.

Parameters:

central - central date

Returns:

array of cached entries surrounding specified date

Throws:

TimeStampedCacheException - if EOP data cannot be retrieved

getLOD

public double getLOD(AbsoluteDate date)

Get the LoD (Length of Day) value.

The data provided comes from the IERS files. It is smoothed data.

Parameters:

date - date at which the value is desired

Returns:

LoD in seconds (0 if date is outside covered range)

getPoleCorrection

public PoleCorrection getPoleCorrection(AbsoluteDate date)

Get the pole IERS Reference Pole correction.

The data provided comes from the IERS files. It is smoothed data.

Parameters:

date - date at which the correction is desired

Returns:

pole correction (PoleCorrection.NULL_CORRECTION if date is outside covered range)

getEquinoxNutationCorrection

public double[] getEquinoxNutationCorrection(AbsoluteDate date)

Get the correction to the nutation parameters for equinox-based paradigm.

The data provided comes from the IERS files. It is smoothed data.

Parameters:

date - date at which the correction is desired

Returns:

nutation correction in longitude ΔΨ and in obliquity Δε (zero if date is outside covered range)

getNonRotatinOriginNutationCorrection

public double[] getNonRotatinOriginNutationCorrection(AbsoluteDate date)

Get the correction to the nutation parameters for Non-Rotating Origin paradigm.

The data provided comes from the IERS files. It is smoothed data.

Parameters:

date - date at which the correction is desired

Returns:

nutation correction in Celestial Intermediat Pole coordinates δX and δY (zero if date is outside covered range)

checkEOPContinuity

public void checkEOPContinuity(double maxGap)
                        throws OrekitException

Check Earth orientation parameters continuity.

Parameters:

maxGap - maximal allowed gap between entries (in seconds)

Throws:

OrekitException - if there are holes in the data sequence

hasDataFor

protected boolean hasDataFor(AbsoluteDate date)

Check if the cache has data for the given date using getStartDate() and getEndDate().

Parameters:

date - the requested date

Returns:

true if the cache has data for the requested date, false otherwise.