fr.cnes.sirius.patrius.bodies

Class JPLHistoricEphemerisLoader

java.lang.Object

fr.cnes.sirius.patrius.bodies.JPLHistoricEphemerisLoader

All Implemented Interfaces:

CelestialBodyEphemerisLoader, JPLEphemerisLoader, Serializable

public class JPLHistoricEphemerisLoader
extends Object
implements JPLEphemerisLoader

Loader for JPL ephemerides binary files (DE 4xx) and similar formats (INPOP 06/08/10). It loads only the CelestialBodyEphemeris. For CelestialPoint loader, see dedicated class.

JPL ephemerides binary files contain ephemerides for all solar system planets.

The JPL ephemerides binary files are recognized thanks to their base names, which must match the pattern [lu]nx[mp]####.ddd (or [lu]nx[mp]####.ddd.gz for gzip-compressed files) where # stands for a digit character and where ddd is an ephemeris type (typically 405 or 406).

Currently accepted JPL formats are: DE200/DE 202/DE 403/DE 405/DE 406/DE 410/DE 413/DE 414/DE 418/DE 421/DE 422/DE 423 and DE 430.

The loader supports files encoded in big-endian as well as in little-endian notation. Usually, big-endian files are named unx[mp]####.ddd, while little-endian files are named lnx[mp]####.ddd.

The IMCCE ephemerides binary files are recognized thanks to their base names, which must match the pattern inpop*.dat (or inpop*.dat.gz for gzip-compressed files) where * stands for any string.

Currently accepted IMCCE formats are: INPOP 06b/06c/08a/10a/10b/10e/13c/17a/19a.

The loader supports files encoded in big-endian as well as in little-endian notation. Usually, big-endian files contain bigendian in their names, while little-endian files contain littleendian in their names.

The loader supports files in TDB or TCB time scales.

Note: the time scale isn't serialized.

Since:

4.10

Author:

Emmanuel Bignon

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_DE_SUPPORTED_NAMES Default supported files name pattern for JPL DE files.
static String	DEFAULT_INPOP_SUPPORTED_NAMES Default supported files name pattern for IMCCE INPOP files.

Constructor Summary

Constructors

Constructor and Description
JPLHistoricEphemerisLoader(String supportedNamesIn, EphemerisType generateTypeIn) Create a loader for JPL ephemerides binary files.

Method Summary

Modifier and Type	Method and Description
double	getLoadedAstronomicalUnit() Get astronomical unit.
double	getLoadedConstant(String... names) Get a constant defined in the ephemerides headers.
double	getLoadedEarthMoonMassRatio() Get Earth/Moon mass ratio.
double	getLoadedGravitationalCoefficient(EphemerisType body) Get the gravitational coefficient of a body.
double	getMaxChunksDuration() Get the maximal chunks duration.
CelestialBodyEphemeris	loadCelestialBodyEphemeris(String name) Load celestial body ephemeris.
static void	setCacheSize(int days) Set ephemeris cache size in days.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_DE_SUPPORTED_NAMES

public static final String DEFAULT_DE_SUPPORTED_NAMES

Default supported files name pattern for JPL DE files.

See Also:

Constant Field Values

DEFAULT_INPOP_SUPPORTED_NAMES

public static final String DEFAULT_INPOP_SUPPORTED_NAMES

Default supported files name pattern for IMCCE INPOP files.

See Also:

Constant Field Values

Constructor Detail

JPLHistoricEphemerisLoader

public JPLHistoricEphemerisLoader(String supportedNamesIn,
                                  EphemerisType generateTypeIn)

Create a loader for JPL ephemerides binary files.

Parameters:

supportedNamesIn - regular expression for supported files names

generateTypeIn - ephemeris type to generate

Method Detail

loadCelestialBodyEphemeris

public CelestialBodyEphemeris loadCelestialBodyEphemeris(String name)
                                                  throws PatriusException

Load celestial body ephemeris.

Specified by:

loadCelestialBodyEphemeris in interface CelestialBodyEphemerisLoader

Parameters:

name - name of the celestial body

Returns:

loaded celestial body

Throws:

PatriusException - if the body cannot be loaded

getLoadedAstronomicalUnit

public double getLoadedAstronomicalUnit()
                                 throws PatriusException

Get astronomical unit.

Returns:

astronomical unit in meters

Throws:

PatriusException - if constants cannot be loaded

getLoadedEarthMoonMassRatio

public double getLoadedEarthMoonMassRatio()
                                   throws PatriusException

Get Earth/Moon mass ratio.

Returns:

Earth/Moon mass ratio

Throws:

PatriusException - if constants cannot be loaded

getLoadedGravitationalCoefficient

public double getLoadedGravitationalCoefficient(EphemerisType body)
                                         throws PatriusException

Get the gravitational coefficient of a body.

Specified by:

getLoadedGravitationalCoefficient in interface JPLEphemerisLoader

Parameters:

body - body for which the gravitational coefficient is requested

Returns:

gravitational coefficient in m³/s²

Throws:

PatriusException - if constants cannot be loaded

getLoadedConstant

public double getLoadedConstant(String... names)
                         throws PatriusException

Get a constant defined in the ephemerides headers.

Note that since constants are defined in the JPL headers files, they are available as soon as one file is available, even if it doesn't match the desired central date. This is because the header must be parsed before the dates can be checked.

There are alternate names for constants since for example JPL names are different from INPOP names (Sun gravity: GMS or GM_Sun, Mercury gravity: GM4 or GM_Mar...).

Parameters:

names - alternate names of the constant

Returns:

value of the constant of NaN if the constant is not defined

Throws:

PatriusException - if constants cannot be loaded

getMaxChunksDuration

public double getMaxChunksDuration()

Get the maximal chunks duration.

Returns:

chunks maximal duration in seconds

setCacheSize

public static void setCacheSize(int days)

Set ephemeris cache size in days. For best performances, cache size should be consistent with consideredd physical timespan. Default value is FIFTY_DAYS.

Parameters:

days - number of days