IlvEllipsoid (Perforce JViews 10.0 API)

java.lang.Object
- ilog.views.maps.projection.IlvEllipsoid

All Implemented Interfaces:

IlvPersistentObject, Serializable
```
public class IlvEllipsoid
extends Object
implements Serializable, IlvPersistentObject
```
This class defines an ellipsoid. Ellipsoids are used in map projections to represent the figure of the earth. For many applications, and especially in small-scale mapping, the earth can be represented as a sphere. However, because the earth rotates on its axis and is slightly flattened, it is better approximated by an ellipsoid of rotation about the polar axis. Ellipsoidal projections are used for accurate large-scale maps and plane coordinate systems.

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`static IlvEllipsoid`	`CPM` The ellipsoid specified by the French Weights and Measures Commission ("Commission des Poids et Mesures") in 1799.
`static IlvEllipsoid`	`SGS85` The ellipsoid used in the Soviet Geodetic System 85
`static IlvEllipsoid`	`SPHERE` A spherical ellipsoid representing the earth.
`static IlvEllipsoid`	`WGS60` The WGS 60 ellipsoid.
`static IlvEllipsoid`	`WGS66` The WGS 66 ellipsoid.
`static IlvEllipsoid`	`WGS72` The WGS 72 ellipsoid.
`static IlvEllipsoid`	`WGS84` The WGS 84 ellipsoid.

Constructor Summary

Constructors
Constructor and Description
`IlvEllipsoid(double radius)` Creates a sphere with the specified radius.
`IlvEllipsoid(double a, double es)` Creates an ellipsoid with the specified equatorial radius and eccentricity.
`IlvEllipsoid(double a, double es, String name, String comment)` Creates a named ellipsoid with the specified equatorial radius and eccentricity.
`IlvEllipsoid(IlvInputStream stream)` Reads the object from an `IlvInputStream`.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`equivalent(IlvEllipsoid e)` Returns `true` if the ellipsoid passed as the argument is equivalent to the object.
`static double`	`ESFromFlattening(double f)` Returns the eccentricity squared which is computed from the flattening of the ellipsoid.
`static double`	`ESFromPolarRadius(double a, double b)` Returns the eccentricity squared which is computed from the semi-major axis and the semi-minor axis of the ellipsoid.
`double`	`getA()` Returns the semi-major axis of the ellipsoid.
`IlvEllipsoid`	`getASphere()` Returns a sphere whose radius is the arithmetic mean of the minor and major axes.
`IlvEllipsoid`	`getASphere(double phi)` Returns a sphere whose radius is the arithmetic mean of the principle radii at the specified latitude.
`double`	`getB()` Returns the semi-minor axis of the ellipsoid.
`String`	`getComment()` Returns a description of the ellipsoid, if available.
`double`	`getES()` Returns the eccentricity squared of the ellipsoid.
`IlvEllipsoid`	`getGSphere()` Returns a sphere whose radius is the geometric mean of the minor and major axes.
`IlvEllipsoid`	`getGSphere(double phi)` Returns a sphere whose radius is the geometric mean of the principle radii at the specified latitude.
`IlvEllipsoid`	`getHSphere()` Returns a sphere whose radius is the harmonic mean of the minor and major axes.
`String`	`getName()` Returns the name of the ellipsoid.
`IlvEllipsoid`	`getSphereOfSameArea()` Returns a sphere of equivalent surface area.
`IlvEllipsoid`	`getSphereOfSameVolume()` Returns a sphere of equivalent volume.
`boolean`	`isSphere()` Returns `true` if the ellipsoid is a sphere.
`String`	`toString()` Converts the ellipsoid to a string.
`void`	`write(IlvOutputStream stream)` Writes the object onto an IlvOutputStream.

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

- Field Detail
  - SPHERE
```
public static final IlvEllipsoid SPHERE
```
    A spherical ellipsoid representing the earth.
    
    See Also:
    
    IlvEllipsoidCollection.getEllipsoids()
  - SGS85
```
public static final IlvEllipsoid SGS85
```
    The ellipsoid used in the Soviet Geodetic System 85
    
    See Also:
    
    IlvEllipsoidCollection.getEllipsoids()
  - CPM
```
public static final IlvEllipsoid CPM
```
    The ellipsoid specified by the French Weights and Measures Commission ("Commission des Poids et Mesures") in 1799.
    
    See Also:
    
    IlvEllipsoidCollection.getEllipsoids()
  - WGS60
```
public static final IlvEllipsoid WGS60
```
    The WGS 60 ellipsoid.
    
    See Also:
    
    IlvEllipsoidCollection.getEllipsoids()
  - WGS66
```
public static final IlvEllipsoid WGS66
```
    The WGS 66 ellipsoid.
    
    See Also:
    
    IlvEllipsoidCollection.getEllipsoids()
  - WGS72
```
public static final IlvEllipsoid WGS72
```
    The WGS 72 ellipsoid.
    
    See Also:
    
    IlvEllipsoidCollection.getEllipsoids()
  - WGS84
```
public static final IlvEllipsoid WGS84
```
    The WGS 84 ellipsoid.
    
    See Also:
    
    IlvEllipsoidCollection.getEllipsoids()
- Constructor Detail
  - IlvEllipsoid
```
public IlvEllipsoid(double radius)
```
    Creates a sphere with the specified radius.
    
    Parameters:
    
    radius - the radius of the sphere in meters
  - IlvEllipsoid
```
public IlvEllipsoid(double a,
                    double es)
```
    Creates an ellipsoid with the specified equatorial radius and eccentricity.
    
    Parameters:
    
    a - semi-major axis of the ellipsoid or equatorial radius
    
    es - eccentricity squared of the ellipsoid
  - IlvEllipsoid
```
public IlvEllipsoid(double a,
                    double es,
                    String name,
                    String comment)
```
    Creates a named ellipsoid with the specified equatorial radius and eccentricity.
    
    Parameters:
    
    a - semi-major axis of the ellipsoid or equatorial radius
    
    es - eccentricity squared of the ellipsoid
    
    name - name of the ellipsoid
    
    comment - a short comment describing the ellipsoid
  - IlvEllipsoid
```
public IlvEllipsoid(IlvInputStream stream)
             throws IlvReadFileException
```
    Reads the object from an IlvInputStream.
    
    Parameters:
    
    stream - the input stream.
    
    Throws:
    
    IlvReadFileException - if the format is not correct.
    
    Since:
    
    JViews 3.0
- Method Detail
  - getA
```
public final double getA()
```
    Returns the semi-major axis of the ellipsoid.
  - getB
```
public final double getB()
```
    Returns the semi-minor axis of the ellipsoid.
  - getES
```
public final double getES()
```
    Returns the eccentricity squared of the ellipsoid.
  - isSphere
```
public boolean isSphere()
```
    Returns true if the ellipsoid is a sphere.
  - getSphereOfSameArea
```
public IlvEllipsoid getSphereOfSameArea()
```
    Returns a sphere of equivalent surface area.
  - getSphereOfSameVolume
```
public IlvEllipsoid getSphereOfSameVolume()
```
    Returns a sphere of equivalent volume.
  - getASphere
```
public IlvEllipsoid getASphere()
```
    Returns a sphere whose radius is the arithmetic mean of the minor and major axes.
  - getASphere
```
public IlvEllipsoid getASphere(double phi)
```
    Returns a sphere whose radius is the arithmetic mean of the principle radii at the specified latitude.
    
    Parameters:
    
    phi - the latitude in radians
    
    See Also:
    
    IlvProjectionUtil.DMSToRadian(java.lang.String), IlvProjectionUtil.DegreeToRadian(double)
  - getGSphere
```
public IlvEllipsoid getGSphere()
```
    Returns a sphere whose radius is the geometric mean of the minor and major axes.
  - getGSphere
```
public IlvEllipsoid getGSphere(double phi)
```
    Returns a sphere whose radius is the geometric mean of the principle radii at the specified latitude.
    
    Parameters:
    
    phi - the latitude in radians.
    
    See Also:
    
    IlvProjectionUtil.DMSToRadian(java.lang.String), IlvProjectionUtil.DegreeToRadian(double)
  - getHSphere
```
public IlvEllipsoid getHSphere()
```
    Returns a sphere whose radius is the harmonic mean of the minor and major axes.
  - ESFromPolarRadius
```
public static double ESFromPolarRadius(double a,
                                       double b)
```
    Returns the eccentricity squared which is computed from the semi-major axis and the semi-minor axis of the ellipsoid.
    
    Parameters:
    
    a - semi-major axis of the ellipsoid or equatorial radius.
    
    b - semi-minor axis of the ellipsoid or polar radius.
  - ESFromFlattening
```
public static double ESFromFlattening(double f)
```
    Returns the eccentricity squared which is computed from the flattening of the ellipsoid.
    
    Parameters:
    
    f - flattening of the ellipsoid.
  - getName
```
public String getName()
```
    Returns the name of the ellipsoid.
  - getComment
```
public String getComment()
```
    Returns a description of the ellipsoid, if available.
  - write
```
public void write(IlvOutputStream stream)
           throws IOException
```
    Writes the object onto an IlvOutputStream.
    
    Specified by:
    
    write in interface IlvPersistentObject
    
    Parameters:
    
    stream - the output stream
    
    Throws:
    
    IOException - thrown when an exception occurs during the write operation for this object.
    
    Since:
    
    JViews 3.0
  - equivalent
```
public boolean equivalent(IlvEllipsoid e)
```
    Returns true if the ellipsoid passed as the argument is equivalent to the object.
    
    Since:
    
    JViews 3.0
  - toString
```
public String toString()
```
    Converts the ellipsoid to a string.
    
    Overrides:
    
    toString in class Object

Class IlvEllipsoid

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

SPHERE

SGS85

CPM

WGS60

WGS66

WGS72

WGS84

Constructor Detail

IlvEllipsoid

IlvEllipsoid

IlvEllipsoid

IlvEllipsoid

Method Detail

getA

getB

getES

isSphere

getSphereOfSameArea

getSphereOfSameVolume

getASphere

getASphere

getGSphere

getGSphere

getHSphere

ESFromPolarRadius

ESFromFlattening

getName

getComment

write

equivalent

toString