AbstractTimeScales (ORbit Extrapolation KIT 10.1 API)

java.lang.Object
- org.orekit.time.AbstractTimeScales

All Implemented Interfaces:

TimeScales

Direct Known Subclasses:

LazyLoadedTimeScales
```
public abstract class AbstractTimeScales
extends Object
implements TimeScales
```
Abstract base class for TimeScales that implements some common functionality.

Since:

10.1

Author:

Evan Ward, Luc Maisonobe

Constructor Summary

Constructors
Constructor and Description

AbstractTimeScales()
Simple constructor.

Constructors
Constructor and Description
`AbstractTimeScales()` Simple constructor.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`AbsoluteDate`	`createBesselianEpoch(double besselianEpoch)` Build an instance corresponding to a Besselian Epoch (BE).
`AbsoluteDate`	`createJulianEpoch(double julianEpoch)` Build an instance corresponding to a Julian Epoch (JE).
`AbsoluteDate`	`getBeidouEpoch()` Reference epoch for BeiDou weeks: 2006-01-01T00:00:00 UTC.
`AbsoluteDate`	`getCcsdsEpoch()` Reference epoch for CCSDS Time Code Format (CCSDS 301.0-B-4): 1958-01-01T00:00:00 International Atomic Time (not UTC).
`protected abstract EOPHistory`	`getEopHistory(IERSConventions conventions, boolean simpleEOP)` Get the EOP history for the given conventions.
`AbsoluteDate`	`getFiftiesEpoch()` Reference epoch for 1950 dates: 1950-01-01T00:00:00 Terrestrial Time.
`AbsoluteDate`	`getFutureInfinity()` Dummy date at infinity in the future direction.
`AbsoluteDate`	`getGalileoEpoch()` Reference epoch for Galileo System Time: 1999-08-22T00:00:00 GST.
`AbsoluteDate`	`getGlonassEpoch()` Reference epoch for GLONASS four-year interval number: 1996-01-01T00:00:00 GLONASS time.
`GMSTScale`	`getGMST(IERSConventions conventions, boolean simpleEOP)` Get the Greenwich Mean Sidereal Time scale.
`AbsoluteDate`	`getGpsEpoch()` Reference epoch for GPS weeks: 1980-01-06T00:00:00 GPS time.
`AbsoluteDate`	`getIrnssEpoch()` Reference epoch for IRNSS weeks: 1999-08-22T00:00:00 IRNSS time.
`AbsoluteDate`	`getJ2000Epoch()` J2000.0 Reference epoch: 2000-01-01T12:00:00 Terrestrial Time (not UTC).
`AbsoluteDate`	`getJavaEpoch()` Java Reference epoch: 1970-01-01T00:00:00 Universal Time Coordinate.
`AbsoluteDate`	`getJulianEpoch()` Reference epoch for julian dates: -4712-01-01T12:00:00 Terrestrial Time.
`AbsoluteDate`	`getModifiedJulianEpoch()` Reference epoch for modified julian dates: 1858-11-17T00:00:00 Terrestrial Time.
`AbsoluteDate`	`getPastInfinity()` Dummy date at infinity in the past direction.
`AbsoluteDate`	`getQzssEpoch()` Reference epoch for QZSS weeks: 1980-01-06T00:00:00 QZSS time.
`protected UT1Scale`	`getUT1(EOPHistory history)` Get the Universal Time 1 scale.
`UT1Scale`	`getUT1(IERSConventions conventions, boolean simpleEOP)` Get the Universal Time 1 scale.

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

Methods inherited from interface org.orekit.time.TimeScales
getBDT, getGLONASS, getGPS, getGST, getIRNSS, getQZSS, getTAI, getTCB, getTCG, getTDB, getTT, getUTC, of

- Constructor Detail
  - AbstractTimeScales
```
public AbstractTimeScales()
```
    Simple constructor.
- Method Detail
  - getUT1
```
protected UT1Scale getUT1(EOPHistory history)
```
    Get the Universal Time 1 scale.
    As this method allow associating any history with the time scale, it may involve large data sets. So this method does not cache the resulting UT1Scale instance, a new instance will be returned each time. In order to avoid wasting memory, calling getUT1(IERSConventions, boolean) with the single enumerate corresponding to the conventions may be a better solution. This method is made available only for expert use.
    
    Parameters:
    
    history - EOP parameters providing dUT1 (may be null if no correction is desired)
    
    Returns:
    
    Universal Time 1 scale
    
    See Also:
    
    getUT1(IERSConventions, boolean)
  - getEopHistory
```
protected abstract EOPHistory getEopHistory(IERSConventions conventions,
                                            boolean simpleEOP)
```
    Get the EOP history for the given conventions.
    
    Parameters:
    
    conventions - to use in computing the EOP history.
    
    simpleEOP - whether to ignore some small tidal effects.
    
    Returns:
    
    EOP history.
  - getUT1
```
public UT1Scale getUT1(IERSConventions conventions,
                       boolean simpleEOP)
```
    Description copied from interface: TimeScales
    
    Get the Universal Time 1 scale.
    
    Specified by:
    
    getUT1 in interface TimeScales
    
    Parameters:
    
    conventions - IERS conventions for which EOP parameters will provide dUT1
    
    simpleEOP - if true, tidal effects are ignored when interpolating EOP
    
    Returns:
    
    Universal Time 1 scale
    
    See Also:
    
    TimeScales.getUTC(), Frames.getEOPHistory(IERSConventions, boolean)
  - getGMST
```
public GMSTScale getGMST(IERSConventions conventions,
                         boolean simpleEOP)
```
    Description copied from interface: TimeScales
    
    Get the Greenwich Mean Sidereal Time scale.
    
    Specified by:
    
    getGMST in interface TimeScales
    
    Parameters:
    
    conventions - IERS conventions for which EOP parameters will provide dUT1
    
    simpleEOP - if true, tidal effects are ignored when interpolating EOP
    
    Returns:
    
    Greenwich Mean Sidereal Time scale
  - getJulianEpoch
```
public AbsoluteDate getJulianEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for julian dates: -4712-01-01T12:00:00 Terrestrial Time.
    Both java.util.Date and DateComponents classes follow the astronomical conventions and consider a year 0 between years -1 and +1, hence this reference date lies in year -4712 and not in year -4713 as can be seen in other documents or programs that obey a different convention (for example the convcal utility).
    
    Specified by:
    
    getJulianEpoch in interface TimeScales
    
    Returns:
    
    Julian epoch.
  - getModifiedJulianEpoch
```
public AbsoluteDate getModifiedJulianEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for modified julian dates: 1858-11-17T00:00:00 Terrestrial Time.
    
    Specified by:
    
    getModifiedJulianEpoch in interface TimeScales
    
    Returns:
    
    Modified Julian Epoch
  - getFiftiesEpoch
```
public AbsoluteDate getFiftiesEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for 1950 dates: 1950-01-01T00:00:00 Terrestrial Time.
    
    Specified by:
    
    getFiftiesEpoch in interface TimeScales
    
    Returns:
    
    Fifties Epoch
  - getCcsdsEpoch
```
public AbsoluteDate getCcsdsEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for CCSDS Time Code Format (CCSDS 301.0-B-4): 1958-01-01T00:00:00 International Atomic Time (not UTC).
    
    Specified by:
    
    getCcsdsEpoch in interface TimeScales
    
    Returns:
    
    CCSDS Epoch
  - getGalileoEpoch
```
public AbsoluteDate getGalileoEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for Galileo System Time: 1999-08-22T00:00:00 GST.
    
    Specified by:
    
    getGalileoEpoch in interface TimeScales
    
    Returns:
    
    Galileo Epoch
  - getGpsEpoch
```
public AbsoluteDate getGpsEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for GPS weeks: 1980-01-06T00:00:00 GPS time.
    
    Specified by:
    
    getGpsEpoch in interface TimeScales
    
    Returns:
    
    GPS Epoch
  - getQzssEpoch
```
public AbsoluteDate getQzssEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for QZSS weeks: 1980-01-06T00:00:00 QZSS time.
    
    Specified by:
    
    getQzssEpoch in interface TimeScales
    
    Returns:
    
    QZSS Epoch
  - getIrnssEpoch
```
public AbsoluteDate getIrnssEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for IRNSS weeks: 1999-08-22T00:00:00 IRNSS time.
    
    Specified by:
    
    getIrnssEpoch in interface TimeScales
    
    Returns:
    
    IRNSS Epoch
  - getBeidouEpoch
```
public AbsoluteDate getBeidouEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for BeiDou weeks: 2006-01-01T00:00:00 UTC.
    
    Specified by:
    
    getBeidouEpoch in interface TimeScales
    
    Returns:
    
    Beidou Epoch
  - getGlonassEpoch
```
public AbsoluteDate getGlonassEpoch()
```
    Description copied from interface: TimeScales
    
    Reference epoch for GLONASS four-year interval number: 1996-01-01T00:00:00 GLONASS time.
    By convention, TGLONASS = UTC + 3 hours.
    
    Specified by:
    
    getGlonassEpoch in interface TimeScales
    
    Returns:
    
    GLONASS Epoch
  - getJ2000Epoch
```
public AbsoluteDate getJ2000Epoch()
```
    Description copied from interface: TimeScales
    
    J2000.0 Reference epoch: 2000-01-01T12:00:00 Terrestrial Time (not UTC).
    
    Specified by:
    
    getJ2000Epoch in interface TimeScales
    
    Returns:
    
    J2000 Epoch
    
    See Also:
    
    AbsoluteDate.createJulianEpoch(double), AbsoluteDate.createBesselianEpoch(double)
  - getJavaEpoch
```
public AbsoluteDate getJavaEpoch()
```
    Description copied from interface: TimeScales
    
    Java Reference epoch: 1970-01-01T00:00:00 Universal Time Coordinate.
    Between 1968-02-01 and 1972-01-01, UTC-TAI = 4.213 170 0s + (MJD - 39 126) x 0.002 592s. As on 1970-01-01 MJD = 40587, UTC-TAI = 8.000082s
    
    Specified by:
    
    getJavaEpoch in interface TimeScales
    
    Returns:
    
    Java Epoch
  - getPastInfinity
```
public AbsoluteDate getPastInfinity()
```
    Description copied from interface: TimeScales
    
    Dummy date at infinity in the past direction.
    
    Specified by:
    
    getPastInfinity in interface TimeScales
    
    Returns:
    
    the earliest date.
  - getFutureInfinity
```
public AbsoluteDate getFutureInfinity()
```
    Description copied from interface: TimeScales
    
    Dummy date at infinity in the future direction.
    
    Specified by:
    
    getFutureInfinity in interface TimeScales
    
    Returns:
    
    the latest date.
  - createJulianEpoch
```
public AbsoluteDate createJulianEpoch(double julianEpoch)
```
    Description copied from interface: TimeScales
    Build an instance corresponding to a Julian Epoch (JE).
    According to Lieske paper: Precession Matrix Based on IAU (1976) System of Astronomical Constants, Astronomy and Astrophysics, vol. 73, no. 3, Mar. 1979, p. 282-284, Julian Epoch is related to Julian Ephemeris Date as:
```
 JE = 2000.0 + (JED - 2451545.0) / 365.25
 
```
    This method reverts the formula above and computes an AbsoluteDate from the Julian Epoch.
    Specified by:
    
    createJulianEpoch in interface TimeScales
    
    Parameters:
    
    julianEpoch - Julian epoch, like 2000.0 for defining the classical reference J2000.0
    
    Returns:
    
    a new instant
    
    See Also:
    
    TimeScales.getJ2000Epoch(), TimeScales.createBesselianEpoch(double)
  - createBesselianEpoch
```
public AbsoluteDate createBesselianEpoch(double besselianEpoch)
```
    Description copied from interface: TimeScales
    Build an instance corresponding to a Besselian Epoch (BE).
    According to Lieske paper: Precession Matrix Based on IAU (1976) System of Astronomical Constants, Astronomy and Astrophysics, vol. 73, no. 3, Mar. 1979, p. 282-284, Besselian Epoch is related to Julian Ephemeris Date as:
```
 BE = 1900.0 + (JED - 2415020.31352) / 365.242198781
 
```
    This method reverts the formula above and computes an AbsoluteDate from the Besselian Epoch.
    Specified by:
    
    createBesselianEpoch in interface TimeScales
    
    Parameters:
    
    besselianEpoch - Besselian epoch, like 1950 for defining the classical reference B1950.0
    
    Returns:
    
    a new instant
    
    See Also:
    
    TimeScales.createJulianEpoch(double)

Class AbstractTimeScales

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.orekit.time.TimeScales

Constructor Detail

AbstractTimeScales

Method Detail

getUT1

getEopHistory

getUT1

getGMST

getJulianEpoch

getModifiedJulianEpoch

getFiftiesEpoch

getCcsdsEpoch

getGalileoEpoch

getGpsEpoch

getQzssEpoch

getIrnssEpoch

getBeidouEpoch

getGlonassEpoch

getJ2000Epoch

getJavaEpoch

getPastInfinity

getFutureInfinity

createJulianEpoch

createBesselianEpoch