Package skyview.geometry

Class CoordinateSystem

java.lang.Object

skyview.geometry.CoordinateSystem

All Implemented Interfaces:

java.io.Serializable, Component

Direct Known Subclasses:

Besselian, Ecliptic, Galactic, ICRS, Julian

public abstract class CoordinateSystem
extends java.lang.Object
implements Component

The class defines coordinate systems in terms of the operations needed to transform the standard coordinate system (currently J2000) to the coordinate system associated with the object. Most coordinate systems will be defined as simple rotations, but some coordinate systems may involve more complext transformations. A factory method is available to generate Coordinate systems from a given string. Typically a string is comprised of an initial and an epoch (e.g., "B1950", "J1975.5"). Any string beginning with "G" is assumed to be Galactic coordinates.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
static CoordinateSystem	B1950	Standard B1950 coordinates
static CoordinateSystem	Gal	Standard Galactic coordinates
static CoordinateSystem	ICRS	Standard ICRS coordinates
static CoordinateSystem	J2000	Standard J2000 coordinates -- the reference frame

Constructor Summary

Constructors

Constructor	Description
CoordinateSystem()

Method Summary

Modifier and Type	Method	Description
static CoordinateSystem	factory(java.lang.String name)	Get a coordinate system by name.
static CoordinateSystem	factory(java.lang.String name, java.lang.String equinox)
abstract Rotater	getRotater()	Get the rotation associated with the projection.
SphereDistorter	getSphereDistorter()	Get the distortion associated with the projection.

Methods inherited from class java.lang.Object

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

Methods inherited from interface skyview.Component

getDescription, getName

Field Detail

J2000

public static final CoordinateSystem J2000

Standard J2000 coordinates -- the reference frame

B1950

public static final CoordinateSystem B1950

Standard B1950 coordinates

Gal

public static final CoordinateSystem Gal

Standard Galactic coordinates

ICRS

public static final CoordinateSystem ICRS

Standard ICRS coordinates

Constructor Detail

CoordinateSystem

public CoordinateSystem()

Method Detail

getRotater

public abstract Rotater getRotater()

Get the rotation associated with the projection.

getSphereDistorter

public SphereDistorter getSphereDistorter()

Get the distortion associated with the projection. By default there is no distortion, but subclasses, notably BesselianProjection, can override this.

factory

public static CoordinateSystem factory(java.lang.String name)

Get a coordinate system by name.

Parameters:

name - A designation of the desired coordinate system. Normally the name is an initial designating the general frame and orientation of the coordinate system followed by an epoch of equinox, e.g., J2000, B1950 E2000.45. The initial letters are:

J

Julian Equatorial Coordinates.

B

Besselian Equatorial Coordinates.

E

Julian Ecliptic Coordinates

H

Helioecliptic coordinates.

G

Galactic coordinates. Only the first letter is parsed.

The name is not case-sensitive.

factory

public static CoordinateSystem factory(java.lang.String name,
                                       java.lang.String equinox)