Get

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Description

The Get command loads data from an external file into a FreeFlyer Object. The external file must be in a supported format.

 

 

Syntax

FreeFlyer Object File

 

Get myVariable from "myVariable.FFObjectFile";

 

Spacecraft State Files

 

Get mySpacecraft as element 3 from "TVHF.report";
 
Get mySpacecraft as ASCII from "SCState.txt" using "SCConfig.txt";

 

Where:

•3 is the element number in "TVHF.report"

•"TVHF.report" is the name of the TCOPS Vector Hold File (TVHF)

•"SCState.txt" is an external ASCII file containing Spacecraft information

•"SCConfig.txt" is the name of the configuration file used to define the contents of the "SCState.txt" file

 

Ephemeris Formats

 

Note: In FreeFlyer 6.0 or higher, use the Ephemeris.LoadEphemeris() method.

 

Get myEphemeris from FFephem "SCephem.FFephem";

Get myEphemeris from CCSDSOEM "SCephem.txt";
Get myEphemeris from STKephem "SCephem.e";
Get myEphemeris from STKAHF "SCephem.a";

 

// Requires NASA Pack

Get myEphemeris from ephem "SCephem.ephem";
Get myEphemeris from PCephem "SCephem.PCephem";

 

Where:

•"SCephem.FFephem" is a FreeFlyer-formatted external ephemeris

•"SCephem.txt" is a CCSDS OEM-formatted external ephemeris

•"SCephem.e" is a STK-formatted external ephemeris

•"SCephem.a" is a STK-formatted attitude history file

•"SCephem.ephem" is a Binary external ephemeris (Requires NASA Pack)

•"SCephem.PCephem" is a PCephem-formatted external ephemeris (Requires NASA Pack)

 

Groundstation Geodetics File

 

Get myGroundStation as station KS2P from "groundstations.dat";

 

Where:

•KS2P is the station Identifier for Kennedy Space Center

•"groundstations.dat" is the name of the Station file

 

Star Field Files

 

Get myStarField as ffstarcatalog from "FFstars.dat";
Get myStarField as skymap from "SMstars.dat";
Get myStarField as openuniverse from "OUstars.dat";

 

Where "<XX>stars.dat" is an external file containing Star Catalog information

 

 

Details

•Any FreeFlyer object can be retrieved from an XML-formatted external file using the syntax: Get <myObjectName> from "myObjectName.FFObjectFile";

•The Object.GetFromFile() or Object.GetFromString() methods can be used in place of the Get command.

•The Put command is used to store object data to external files, which can be retrieved with the Get command.

•The Put and Get commands provide similar functionality to the Save and Restore commands, while saving object data to external files instead of internal memory.

•When retrieving data for a Spacecraft object, the Get command will only import the spacecraft's properties, not its attached objects (such as tanks and sensors).

•The Get command can not be used with Lists or Formations.

 

•Copying objects:

•The Assignment command can be used to set all the properties of one object equal to those of another object.

oThe Assignment command only supports certain object types: Variables, Arrays, Strings, StringArrays, Spacecraft, and GroundStations.

oThe Assignment command does not equalize the properties of any attached objects or subsystems (such as Propagators, ForceModels, Tanks, Thrusters, Sensors, and Antennas).

•One way to copy objects or subsystems that are not supported by the Assignment command is to use the Put and Get commands to put the first object out to a file and then load all the properties back in to a second object.

oThe example below shows how to equalize all the properties of two Spacecraft's Propagators and ForceModels:

 

// Use the Assigment command to copy Spacecraft1's properties into Spacecraft2

Spacecraft2 = Spacecraft1;

 

// Put Spacecraft1's Propagator and ForceModel to files

Put (Spacecraft1.Propagator AsType RK89) to "prop.FFObjectFile";

Put (Spacecraft1.Propagator AsType RK89).ForceModel to "fm.FFObjectFile";

 

// Retrieve data from files into Spacecraft2's Propagator and ForceModel

Get (Spacecraft2.Propagator AsType RK89) from "prop.FFObjectFile";

Get (Spacecraft2.Propagator AsType RK89).ForceModel from "fm.FFObjectFile";

 

 

Command Editor

Object

•Specifies the FreeFlyer Object that you would like to retrieve from an external file

  Spacecraft

•Type of Get: Specifies the type of external file from which the object is to be retrieved

oFreeFlyer Object File

oFile: Specifies the path and filename of the FreeFlyer Object file

oTCOPS Vector Hold File (TVHF) (NASA Pack only)

▪Element: Specifies the location in the file from which to retrieve Spacecraft data

▪File: Specifies the path and filename of the TVHF

oASCII File

▪File: Specifies the path and filename of the ASCII-formatted file

▪Config File: Specifies the path and filename of the configuration file used to define the format of the ASCII file

  GroundStation

•Type of Get: Specifies the type of external file from which the GroundStation is to be retrieved

oStation Geodetics File

▪Station: Specifies the desired GroundStation by its four-letter Acronym

▪File: Specifies the path and filename of the Station Geodetics file

▪FreeFlyer Object File

•File: Specifies the path and filename of the FreeFlyer Object file

Ephemeris

•Type of Get: Specifies the type of external ephemeris file from which the Ephemeris is to be retrieved

oGSFC Ephem (UNIX) (NASA Pack only): UNIX-formatted Goddard Space Flight Center (GSFC) ephemeris

oGSFC Ephem (PC) (NASA Pack only): PC-formatted Goddard Space Flight Center (GSFC) ephemeris

oFreeFlyer ephem: FreeFlyer-formatted ephemeris

oSTK ephem: STK-formatted ephemeris (.e file)

oSTK AHF: STK-formatted Attitude History File (.a file)

oCCSDS OEM

oFreeFlyer Object File

•File: Specifies the path and filename of the external file from which the Ephemeris data is to be retrieved

StarField

•Type of Get: Specifies the format of the external file from which StarField information is to be retrieved

oStarField

▪Type: Defines the type of StarField-formatted file

❖skymap

❖openuniverse

❖ffstarcatalog: FreeFlyer Star Catalog format

▪FreeFlyer Object File

•File: Specifies the path and filename of the StarField-formatted file

Any other object

•File: Specifies the path and filename of the external file from which the Object data is to be retrieved

otext

oString object

 

Script

•Displays the FreeFlyer Script that is generated by the editor

 

Description

•Displays descriptions of the editor and its fields

•Description text changes as the mouse pointer moves over the different fields within the editor

 

 

 

 

Deprecated

Spacecraft State Files

 

Note: This syntax has been deprecated as of FreeFlyer version 6.0. See Working with TLEs and the SGP4 Propagator for updated syntax.

 

Get mySpacecraft as NORAD 2 from "NORAD.txt";
Get mySpacecraft as NORAD 2 from "NORAD.txt" using "NORADconfig.txt";
Get mySpacecraft as NORAD Next from "NORAD.txt" using "NORADconfig.txt";
Get mySpacecraft as NORAD 2 from "NORAD.txt" using "NORADconfig.txt" named "myString";

 

Where:

•2 and Next define the state from the NORAD file

•"NORAD.txt" is an external NORADSGP4-formatted file containing Spacecraft information

•"NORADconfig.txt" is the name of the configuration file used to define the contents of the "NORAD.txt" file

 

 

See Also

•Put Command

•Save Command

•Restore Command

•Data Files Reference