spice.basic
Class GF

java.lang.Object
  spice.basic.GF

Direct Known Subclasses:

GFBinaryStateSearch, GFNumericSearch

public abstract class GF
extends java.lang.Object

Class GF is the root class of the JNISpice Geometry Finder subsystem. This subsystem finds times when specific geometric conditions are met.

See the subclasses of GFNumericSearch and GFBinaryStateSearch for the methods used to perform searches.

Version 1.0.0 29-NOV-2016 (NJB)

Field Summary

static double	ADDWIN ADDWIN is a parameter used in numeric quantity searches that use an equality constraint.
static java.lang.String	ANNULR Parameter identifying an "annular occultation." This geometric condition is more commonly known as a "transit." The limb of the background object must not be blocked by the foreground object in order for an occultation to be "annular."
static java.lang.String	ANY Parameter identifying any type of occultation or transit.
static java.lang.String	CIRFOV Parameter identifying a circular FOV.
static double	CNVTOL is the default convergence tolerance used by GF routines that don't support a user-supplied tolerance value.
static java.lang.String	EDSHAP Parameter indicating a target object's shape is modeled as an ellipsoid.
static java.lang.String	ELLFOV Parameter identifying an elliptical FOV.
static java.lang.String	FULL Parameter identifying a full occultation: the foreground body entirely blocks the background body.
static double	MARGIN A small positive number used to constrain the orientation of the boundary vectors of polygonal FOVs.
static int	MAXVRT Maximum allowed number of boundary vectors for a polygonal FOV.
static java.lang.String	PARTL Parameter identifying a "partial occultation." This is an occultation in which the foreground body blocks part, but not all, of the limb of the background body.
static java.lang.String	POLFOV Parameter identifying a polygonal FOV.
static java.lang.String	PTSHAP Parameter indicating a target object's shape is modeled as a point.
static java.lang.String	RECFOV Parameter identifying a rectangular FOV.
static java.lang.String	RYSHAP Parameter indicating a target object's "shape" is modeled as a ray emanating from an observer's location.
static java.lang.String	SPSHAP Parameter indicating a target object's shape is modeled as a sphere.

Constructor Summary

GF()

Method Summary

static void

setTolerance(TDBDuration tol) Set the convergence tolerance of the GF subsystem.

Methods inherited from class java.lang.Object

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

Field Detail

MAXVRT

public static final int MAXVRT

Maximum allowed number of boundary vectors for a polygonal FOV.

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Constant Field Values

CIRFOV

public static final java.lang.String CIRFOV

Parameter identifying a circular FOV.

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Constant Field Values

ELLFOV

public static final java.lang.String ELLFOV

Parameter identifying an elliptical FOV.

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Constant Field Values

POLFOV

public static final java.lang.String POLFOV

Parameter identifying a polygonal FOV.

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Constant Field Values

RECFOV

public static final java.lang.String RECFOV

Parameter identifying a rectangular FOV.

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Constant Field Values

MARGIN

public static final double MARGIN

A small positive number used to constrain the orientation of the boundary vectors of polygonal FOVs. Such FOVs must satisfy the following constraints:

    1)  The boundary vectors must be
        contained within a right circular
        cone of angular radius less than
        than (pi/2) - MARGIN radians; in
        other words, there must be a vector
        A such that all boundary vectors
        have angular separation from A of
        less than (pi/2)-MARGIN radians.

    2)  There must be a pair of boundary
        vectors U, V such that all other
        boundary vectors lie in the same
        half space bounded by the plane
        containing U and V. Furthermore, all
        other boundary vectors must have
        orthogonal projections onto a plane
        normal to this plane such that the
        projections have angular separation
        of at least 2*MARGIN radians from
        the plane spanned by U and V.
   

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Constant Field Values

ANNULR

public static final java.lang.String ANNULR

Parameter identifying an "annular occultation." This geometric condition is more commonly known as a "transit." The limb of the background object must not be blocked by the foreground object in order for an occultation to be "annular."

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Constant Field Values

ANY

public static final java.lang.String ANY

Parameter identifying any type of occultation or transit.

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Constant Field Values

FULL

public static final java.lang.String FULL

Parameter identifying a full occultation: the foreground body entirely blocks the background body.

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Constant Field Values

PARTL

public static final java.lang.String PARTL

Parameter identifying a "partial occultation." This is an occultation in which the foreground body blocks part, but not all, of the limb of the background body.

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Constant Field Values

EDSHAP

public static final java.lang.String EDSHAP

Parameter indicating a target object's shape is modeled as an ellipsoid.

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Constant Field Values

PTSHAP

public static final java.lang.String PTSHAP

Parameter indicating a target object's shape is modeled as a point.

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Constant Field Values

RYSHAP

public static final java.lang.String RYSHAP

Parameter indicating a target object's "shape" is modeled as a ray emanating from an observer's location. This model may be used in visibility computations for targets whose direction, but not position, relative to an observer is known.

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Constant Field Values

SPSHAP

public static final java.lang.String SPSHAP

Parameter indicating a target object's shape is modeled as a sphere.

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Constant Field Values

ADDWIN

public static final double ADDWIN

ADDWIN is a parameter used in numeric quantity searches that use an equality constraint. This parameter is used to expand the confinement window (the window over which the search is performed) by a small amount at both ends. This expansion accommodates the case where a geometric quantity is equal to a reference value at a boundary point of the original confinement window.

Units are TDB seconds.

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Constant Field Values

CNVTOL

public static final double CNVTOL

is the default convergence tolerance used by GF routines that don't support a user-supplied tolerance value. GF searches for roots will terminate when a root is bracketed by times separated by no more than this tolerance.

Units are TDB seconds.

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Constant Field Values

Constructor Detail

GF

public GF()

Method Detail

setTolerance

public static void setTolerance(TDBDuration tol)
                         throws SpiceException

Set the convergence tolerance of the GF subsystem.

Throws:

SpiceException