WsfCovariance

WsfCovariance inherits Object

WsfCovariance encapsulates the ability to receive information from State and Measurement Covariance Matrices associated with particular target tracks.

Methods

double MajorAxis()

Returns the length of the major axis (in meters) of the associated error ellipse.

Note

In the deprecated form, the supplied track object is used to extract some data required for a coordinate conversion. This should be the same track from which the covariance matrix was extracted.

double MinorAxis()

Returns the length of the minor axis (in meters) of the associated error ellipse.

Note

In the deprecated form, the supplied track object is used to extract some data required for a coordinate conversion. This should be the same track from which the covariance matrix was extracted.

double Bearing()

Returns the bearing (orientation) angle (in degrees) of the associated error ellipse.

Note

In the deprecated form, the supplied track object is used to extract some data required for a coordinate conversion. This should be the same track from which the covariance matrix was extracted.

double Trace()

Returns the trace (sum of the main diagonal) of the particular covariance matrix.

Ellipsoid EllipsoidNED()

Return the ellipsoid corresponding to the NED (North/East/Down) frame of the covariance’s stored location. The returned Ellipsoid object can be used to render the ellipsoid with WsfDraw.

WsfCovariance CovarianceAtTime(double aSimTime)

Returns a new state covariance matrix that represents the state covariance matrix as of the last track update propagated forward to the specified time. If the supplied time is less than the last update time of the track, the state covariance from the last track update will be returned.

Note

The return value will be invalid if sufficient information does not exist in the source object. It should be tested with the WsfObject.IsValid method prior to being used.

Note

In the deprecated form, the supplied track object is used to extract some data required for a coordinate conversion. This should be the same track from which the covariance matrix was extracted.

Example:

WsfCovariance covAtLastUpdate = TRACK.StateCovariance();
WsfCovariance covNow          = covAtLastUpdate.CovarianceAtTime(TIME_NOW);
if (covNow.IsValid())
{
   // OK to use...
}

Vec3 CenterLocation()

Returns the estimated location, in world coordinates (WCS), of the center of the associated error ellipsoid. In the case that no location is available, the returned vector will contain all zeros.

int Rows()

Returns the number of rows in the covariance matrix.

int Columns()

Returns the number of columns in the covariance matrix.

double Element(int aRow, int aColumn)

Returns a specific element from the covariance matrix.