MarkPoint

General Mission Analysis Tool

MarkPoint

MarkPoint — Allows you to add a special mark point character on an XYPlot

Script Syntax

MarkPoint  OutputNames

OutputNames
  OutputNames is the list of subscribers and a special mark point
  will be added to each subscriber’s XYPlot. When mark points need
  to be added to multiple subscribers, then the subscribers need
  to be separated by a space.

Description

The MarkPoint command allows you to add a special mark point character to highlight a single data point on an XYPlot. MarkPoint command works only for XYPlot subscriber. This command also allows you to add special mark points on multiple XYPlot resources. MarkPoint command can be used through GMAT’s GUI or the script interface.

Options

Option

Description

OutputNames

The MarkPoint command allows the user to add a special mark point character to highlight an individual data point on an XYPlot.

Accepted Data Types	Resource reference
Allowed Values	XYPlot resource
Default Value	DefaultXYPlot
Required	yes
Interfaces	GUI, script

GUI

Figure below shows default settings for MarkPoint command:

Remarks

GMAT allows you to insert MarkPoint command into the Mission tree at any location. This allows you to add special mark points on an XYPlot at any point in your mission. The XYPlot subscriber plots data at each propagation step of the entire mission duration. If you to want to place mark points on an XYPlot at specific points, then a MarkPoint command can be inserted into the mission sequence to control when mark points are placed onto an XYPlot. Refer to the Examples section below to see how MarkPoint command can be used in the Mission tree.

Examples

This example shows how to use MarkPoint command on multiple subscribers. Mark points are added on two XYPlots after every 0.2 days through an iterative loop:

          Create Spacecraft aSat
Create Propagator aProp

Create XYPlot aPlot1 aPlot2

aPlot1.XVariable = aSat.A1ModJulian
aPlot1.YVariables = {aSat.EarthMJ2000Eq.X}

aPlot2.XVariable = aSat.A1ModJulian
aPlot2.YVariables = {aSat.EarthMJ2000Eq.VX}

BeginMissionSequence;

While aSat.ElapsedDays < 1.0
 MarkPoint aPlot1 aPlot2
 Propagate aProp(aSat) {aSat.ElapsedDays = 0.2}
EndWhile

This example shows how to use MarkPoint on a single subscriber. In this example, mark points are placed on the XYPlot the moment spacecraft’s altitude goes below 750 Km. Note that mark points are placed on the XYPlot at every integration step:

          Create Spacecraft aSat
Create Propagator aProp

Create XYPlot aPlot1

aPlot1.XVariable = aSat.A1ModJulian
aPlot1.YVariables = {aSat.Earth.Altitude}

BeginMissionSequence

While aSat.ElapsedDays < 2
 Propagate aProp(aSat)
 If aSat.Earth.Altitude < 750
 MarkPoint aPlot1
 EndIf
EndWhile

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