JEphem Presentation Ephemeris SkyMap Curve Informatic Library Download Glossary About | |
JEphem Ephemeris trail Class organization |
|
Class organization |
Now that we know how to get the coordinates of the celestial bodies, we can have a first glance at the program organization.
more details will be given in the page "Putting all together". |
jephem.astro.solarsystem.VSOP87.java
jephem.astro.solarsystem.elp82.ELP82.java
jephem.astro.solarsystem.Pluto99.java
Pluto99
is autonom, but VSOP87
and ELP82
use other files ; this is summarized in the following diagram :
All these classes are in the package jephem.astro.solarsystem or its sub-packages.
The text files containing data are in directory JEphem/data/astro/planets . See JEphem directories for more information about data directory.
|
Body.java
and AstroContext.java
in package jephem.astro
.
Body
is a class representing a celestial body, used to memorize the coordinates. One field (index
) permits to know which planet the body refers to. For this, an integer is used. All classes of JEphem use constants of SolarSystemConstants
to identify celestial bodies.
AstroContext
is the conductor of ephemeris calculation, the central class. It handles the date for which the computation is asked (jd
), and an array of bodies.
AstroContext.calcBodyCoords()
. One of the tasks of AstroContext
is to call the low-level classes in function of the bodies it is handling.
jephem.astro.AstroContext
is characterized by its julian day and its bodies. As always in JEphem, the variables holding these data are private, and accessible via public methods.
whichBody
is expressed with constants of SolarSystemConstants
.