ReportFile

Behavior When using Filename field

GMAT allows you to specify the name of the report file in two ways. The default naming convention for a report file when using FileName field is shown below:

          Create ReportFile aReport
aReport.Filename = 'ReportFile1.txt'
aReport.WriteReport = true
        

An alternate method for naming a report file is to name the file without using any single quotes around the report file’s name.

          Create ReportFile aReport
aReport.Filename = ReportFile1.txt
aReport.WriteReport = true
        

How data is reported to a report file

GMAT allows you to report data to a report file in two ways: You can use ReportFile.Add field or a Report command.

You can add data using the .Add field of ReportFile resource and this method reports data to the report file at each propagation step. Below is an example script snippet that shows how to report epoch and selected orbital elements using the .Add field:

          Create Spacecraft aSat
Create ReportFile aReport

aReport.Add = {aSat.UTCGregorian aSat.Earth.SMA, aSat.Earth.ECC, ...
aSat.Earth.TA, aSat.EarthMJ2000Eq.RAAN}

Create Propagator aProp

BeginMissionSequence
Propagate aProp(aSat) {aSat.ElapsedSecs = 8640.0}
        

GMAT’s ReportFile.Add field will not report selected data to the report file at each propagation step if Propagate command is not included under the BeginMissionSequence.

An alternative method of reporting data to the report file is via the Report command. Using the Report command allows you to report data to the report file at specific points in your mission. Below is an example script snippet that shows how to report epoch and selected orbital elements using the Report command:

          Create Spacecraft aSat
Create ReportFile aReport

Create Propagator aProp

BeginMissionSequence

Report aReport aSat.UTCGregorian aSat.Earth.SMA aSat.Earth.ECC ...
aSat.Earth.TA aSat.EarthMJ2000Eq.RAAN

Propagate aProp(aSat) {aSat.ElapsedSecs = 8640.0}

Report aReport aSat.UTCGregorian aSat.Earth.SMA aSat.Earth.ECC ...
aSat.Earth.TA aSat.EarthMJ2000Eq.RAAN
        

Behavior and Interactions when using ReportFile Resource & Report Command

Suppose you utilize a ReportFile resource and opt not to write a report and select false for the field name WriteReport, as shown in the example below:

          Create ReportFile aReport
aReport.Filename = ReportFile1.txt
aReport.Add = {aSat.A1ModJulian, aSat.Earth.SMA}
aReport.WriteReport = false
        

Now assume that at the same time, you decide to utilize Report command in the Mission tree, as shown in the example script snippet below:

          BeginMissionSequence;
Report aReport aSat.A1ModJulian aSat.Earth.SMA aSat.Earth.ECC
Propagate aProp(aSat) {aSat.Earth.Periapsis}
Report aReport aSat.A1ModJulian aSat.Earth.SMA aSat.Earth.ECC
        

At this point, you may think that since false option is selected under the field name WriteReport in ReportFile resource, hence GMAT will not generate the report file called ReportFile1.txt. On the Contrary, GMAT will generate a report called ReportFile1.txt, but this report will only contain data that was requested using the Report command. ReportFile1.txt text file will contain epoch, semi-major-axis and eccentricity only at specific points of the mission.

Behavior when reporting data in Iterative Processes

GMAT allows you to specify how data is written to reports during iterative processes such as differential correction or optimization. SolverIterations field of ReportFile resource supports 3 options which are described in the table below:

Where Reports are written

GMAT allows you to write reports to any desired path or location. You can do this by going to GMAT’s startup file called gmat_startup_file.txt and define an absolute path under OUTPUT_PATH. This allows you to save report files in the directory of your choice as oppose to saving report files in GMAT's default Output folder. In ReportFile.FileName field, If no path is provided and only name of the report file is defined, then report files are written to GMAT's default Output folder. The default path where reports are written to is the Output folder located in the main directory where GMAT is installed.

Below is an example script snippet that shows where generated reports are written when only report file’s name is provided under the FileName field. In this example, 'ReportFile1.txt'report is written to the Output folder located in the main directory where GMAT is installed:

          Create ReportFile aReport

aReport.Filename = 'ReportFile1.txt'
aReport.Add = {aSat.A1ModJulian, aSat.Earth.ECC}
        

An alternate method where report files can be written is by defining a relative path. You can define the relative path in GMAT’s startup file gmat_startup_file.txt under OUTPUT_PATH. For example, you can set a relative path by setting OUTPUT_PATH = C:/Users/rqureshi/Desktop/GMAT/mytestfolder/../output2/. In this path, the syntax ".." means to “go up one level”. After saving the startup file, when the script is executed, the generated report file named under FileName field will be written to a path C:\Users\rqureshi\Desktop\GMAT\output2.

Another method where report files can be written to is by defining an absolute path in GMAT’s startup file gmat_startup_file.txt under OUTPUT_PATH. For example, you can set an absolute path by setting OUTPUT_PATH = C:/Users/rqureshi/Desktop/GMAT/mytestfolder/. When the script is executed, report file named under FileName field will be written to an absolute path C:\Users\rqureshi\Desktop\GMAT\mytestfolder.

Instead of defining a relative or an absolute path in GMAT's startup file, you can choose to define an absolute path under FileName field too. For example, if you set ReportFile.FileName = C:\Users\rqureshi\Desktop\GMAT\mytestfolder\ReportFile.txt, then report file will be saved in mytestfolder.

Behavior when using ReportFile Resource & Toggle Command

GMAT allows you to use Toggle command while using the Add field of ReportFile resource. When Toggle Off command is issued for a ReportFile, not data is sent to a report file until a Toggle On command is issued. Similarly, when a Toggle On command is used, data is sent to a report file at each integration step until a Toggle Off command is used.

Below is an example script snippet that shows how to use Toggle Off and Toggle On command while using the ReportFile resource. Spacecraft’s cartesian position vector is reported to the report file.

          Create Spacecraft aSat
Create Propagator aProp

Create ReportFile aReport
aReport.Filename = 'ReportFile1.txt'
aReport.Add = {aSat.UTCGregorian, aSat.EarthMJ2000Eq.X ...
aSat.EarthMJ2000Eq.Y aSat.EarthMJ2000Eq.Z}

BeginMissionSequence

Toggle aReport Off
Propagate aProp(aSat) {aSat.ElapsedDays = 2}
Toggle aReport On
Propagate aProp(aSat) {aSat.ElapsedDays = 4}
        

Behavior When Specifying Empty Brackets in ReportFile's Add Field

When using ReportFile.Add field, GMAT does not allow brackets to be left empty. The brackets must always be populated with values that you wish to report. If brackets are left empty, then GMAT throws in an exception. Below is a sample script snippet that shows an example of empty brackets. If you were to run this script, then GMAT throws in an execption reminding you that brackets cannot be left empty.

          Create Spacecraft aSat
Create Propagator aProp
Create ReportFile aReport

aReport.Add = {}

BeginMissionSequence
Propagate aProp(aSat) {aSat.ElapsedSecs = 8640.0}
        

Propagate an orbit and write cartesian state to a report file at every integrator step

          Create Spacecraft aSat
Create Propagator aProp

Create ReportFile aReport
GMAT aReport.Filename = 'ReportFile1.txt'
aReport.Add = {aSat.EarthMJ2000Eq.X aSat.EarthMJ2000Eq.Y ...
aSat.EarthMJ2000Eq.Z aSat.EarthMJ2000Eq.VX ...
aSat.EarthMJ2000Eq.VY aSat.EarthMJ2000Eq.VZ}

BeginMissionSequence

Propagate aProp(aSat) {aSat.ElapsedSecs = 8640.0}

        

Propagate an orbit for 1 day and write cartesian state to a report file at specific points in your mission

          Create Spacecraft aSat
Create Propagator aProp

Create ReportFile aReport
GMAT aReport.Filename = 'ReportFile1.txt'

BeginMissionSequence

Report aReport aSat.EarthMJ2000Eq.X aSat.EarthMJ2000Eq.Y ...
aSat.EarthMJ2000Eq.Z aSat.EarthMJ2000Eq.VX ...
aSat.EarthMJ2000Eq.VY aSat.EarthMJ2000Eq.VZ

Propagate aProp(aSat) {aSat.ElapsedDays = 1}

Report aReport aSat.EarthMJ2000Eq.X aSat.EarthMJ2000Eq.Y ...
aSat.EarthMJ2000Eq.Z aSat.EarthMJ2000Eq.VX ...
aSat.EarthMJ2000Eq.VY aSat.EarthMJ2000Eq.VZ