PointGroup.Coverage(Spacecraft, Array, Array, TimeSpanArray) Method

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Description

This method provides sensor coverage analysis for the set of points defined by a PointGroup. This can be used to determine what parts of the central body can be seen by a given sensor at some point in time, using the current epoch of the specified Spacecraft. The coverage analysis can be extended over a period of time by calling this method inside a propagation loop. When specifying Spacecraft arguments, up to 50 Spacecraft can be included in the analysis. The active Sensors on each Spacecraft will be used to determine coverage.

 

Array output arguments are used to capture the statistics of the coverage analysis. Do not use these arrays as output arguments for more than one method. Note that the dimensions of the argument arrays are set when the Coverage method is first called; the dimension is not reset by subsequent calls. The Coverage method returns a flag indicating whether the coverage has changed since the last method call. This can be used to increase performance by indicating that further analysis is not necessary if the coverage statistics have not changed.

 

Timing Precision Mode

This page describes functionality in nanosecond timing precision mode.

 

Note: This method has a state. See the Methods and Properties with State page for more information.

 

Method Signature

PointGroup.Coverage(

Spacecraft spacecraft,


Array coverageArray,


Array revisitStatisticsArray,


TimeSpanArray timeStatisticsArray)

 

Arguments

spacecraft


Description:

Spacecraft whose Sensors will be used for the coverage analysis. Up to 50 Spacecraft can be specified.

Repeatable:

1 to 50 times

 

coverageArray


Description:

This array holds the coverage for the entire set of Sensors. A zero indicates the point has never been in view of any Sensor of the set. A one indicates the point has been in view of at least one Sensor of the set.

 

revisitStatisticsArray


Description:

This array contains two statistics of the revisits of the points. A visit is defined as an interval in which a point is continually in view of any single Sensor. A revisit is the reoccurrence of a visit with the revisit time as the time elapsed between the beginning of subsequent visits. Points are numbered from 0 to ( PointGroup.NumberOfPoints - 1 ).

 

Statistic #1 - number of times a point has had visits. The array index for point number M is ( pointNumber ).

Statistic #2 - sum of the square of the time between visits. The array index for a point is ( 1 x PointGroup.NumberOfPoints + pointNumber ).

 

timeStatisticsArray


Description:

This array contains five time statistics of the revisits of the points. A visit is defined as an interval in which a point is continually in view of any single Sensor. A revisit is the reoccurrence of a visit with the revisit time as the time elapsed between the beginning of subsequent visits. The revisit time is reported in units of days. Points are numbered from 0 to ( PointGroup.NumberOfPoints - 1 ). All values contained in this array will have Nanosecond precision.

 

Statistic #1 - average time between visits. The array index for point number M is ( pointNumber ).

Statistic #2 - last revisit time. The array index for a point is ( 1 x PointGroup.NumberOfPoints + pointNumber ).

Statistic #3 - epoch of the beginning of the last visit. The array index for a point is ( 2 x PointGroup.NumberOfPoints + pointNumber ).

Statistic #4 - maximum time between visits. The array index for a point is ( 3 x PointGroup.NumberOfPoints + pointNumber ).

Statistic #5 - minimum time between visits. The array index for a point is ( 4 x PointGroup.NumberOfPoints + pointNumber ).

 

 

Return Value

Type:

number

 

Returns a 1 if the coverage has changed since the last method call, and a 0 if coverage has not changed.

 

Syntax

myVariable1 = myPointGroup1.Coverage(mySpacecraft1, myArray1, myArray2, myTimeSpanArray1);

 

See also

PointGroup Object

PointGroup.Coverage

Coverage and Contact Analysis Guide

PointGroups Guide