Description | Example | Return message | Group


Allow for the association and management of time ordered data computed outside of STK with STK objects.


ExternalData <ObjectPath> {DataOption} [<Parameters>]


The purpose of this command is to allow for the association and management of time ordered data computed outside of STK with STK objects. Data associated with STK objects via the ExternalData command can be accessed through the normal STK data providing mechanism and is therefore available for use in reporting, graphing, dynamic displays, strip charts and data displays in the 3D graphics window. This command is useful for the real time display of telemetry information on the 3D graphics window.

The ExternalData command adds the information that you provide under a Data Provider called 'User Supplied Data'. Go to Object Tools -> Report, and click the 'New' button to see the Data Provider list and create a new report style that contains your custom data.

AddGroup"<GroupName>" <NumberOfVariables> ("<VariableName>" "<Dimension>") ... Create a new time ordered data group to the specified object. A data group is set of time dependent variables that will all be set at the same time. A <GroupName> must be specified along with the <NumberOfVariables> in the group. Paired <VariableName> and <Dimension> values follow. <VariableName> and <Dimension> must be enclosed in quotes if there are spaces in their names. The list of available <Dimensions> may be taken from the SetGUIUnits command. All variables in a data group are required to be set at the same time.

To create a <Variable> of string data, use "Char" for the <Dimension>.

If your data is unitless, use "Custom" for the Dimension in the VariableName-Dimension pair, and use "" (an empty string) for the "<UnitAbbr>" in the SetInputUnit {DataOption} (below).

AddData"<GroupName>" "{TimeValue}" <Variable> <Variable2> ...Adds an additional entry into the time ordered Table of data for the specified data group. The data group must already have been created. All variables in the data group must be given a value and the order of those values must be the same as used in the creation of the data group.

For valid {TimeValue} values see Time Options.

For a variable whose dimension is Char, the value must be entered in quotes: "<Variable>"

The <Variables> entered must be valid values based on the unit selected. If the unit conversion can not be completed successfully, the command will Nack.

ReadFile"<FilePath>" [Save | NoSave]Read in data groups from the specified External Data file. External Data files must follow the appropriate format for compatibility with STK; refer to the STK desktop application help for information about proper file formatting. By default, data read in from a file is not saved with STK object, but this behavior is subject to explicit override by specifying either the Save or NoSave optional keywords.
DeleteGroup"<GroupName>"Deletes the specified data group and all data contained therein.
FlushGroup"<GroupName>"Removes all data entries from the specified data group, but leaves the definition of the group intact.
ReferenceEpochFormat"<ReferenceEpochFormat>"Allows a format other than UTCG to specify the epoch. Without this keyword, the ReferenceEpoch is assumed to be UTCG.
SetInterpOrder"<GroupName>" "<VariableName>" <InterpOrder>Sets the interpolation order for the specified variable in the specified data group. The default is 1st order interpolation.
SetInputUnit"<GroupName>" ("<VariableName>" "<UnitAbbr>") ... Sets the input unit(s) for the dimension of the specified variable in the specified data group. The unit specification is done using the unit abbreviation strings used in the STK GUI. The set of available abbreviation strings for a given dimension are outlined in the SetGUIUnits command. If a dimension is compound, such as the "Rate" dimension, then the units for each sub-dimension are specified in separate commands, see example below. Available compound dimensions include:
  • "AngleRateUnit"
  • "AngleAccelUnit"
  • "Angle Squared"
  • "Area"
  • "Small Area"
  • "Area Rate"
  • "Area Per Mass"
  • "Rate"
  • "Acceleration"
  • "Speed Change"
  • "Rate Squared"
  • "Mass Per Time"
  • "Force Per Time"
  • "TorqueUnit"
  • "AngMomemtumUnit"
  • "Volume"
  • "Density"

If your data is unitless or character data, use "" (an empty string) for the "<UnitAbbr>".

SetThinningInterval"<GroupName>" <TimeStep>Sets the data thinning parameter for the specified data group. This parameter dictates minimum number of seconds which must elapse between the time stamps of incoming data sets before the new data is permanently stored. The last data set is always stored when thinning is used, but may be deleted when a new data set comes in. The default thinning interval is zero, meaning that all incoming data is retained.

The <VariableName>, <Dimension> and <UnitAbbr> values must be enclosed in quotes only if there are spaces in their names.


ExternalData */Satellite/Sat1 AddGroup "My Data" 2 Fuel Mass Spin Rate
ExternalData */Satellite/Sat1 SetInputUnit "My Data" Spin km Spin min
ExternalData */Satellite/Sat1 SetInterpOrder "My Data" Spin 2
ExternalData */Satellite/Sat1 SetThinningInterval "My Data" 10.0
ExternalData */Satellite/Sat1 AddData "My Data" "1 Jun 2002 00:00:00.00" 303.25 4.2938
ExternalData */Satellite/Sat1 AddData "My Data" "1 Jun 2002 00:00:15.22" 302.02 4.4522
ExternalData */Satellite/Sat1 FlushGroup "My Data"
ExternalData */Satellite/Sat1 DeleteGroup "My Data"

The following examples pertain to unitless data:

ExternalData */Facility/f1 AddGroup "LinearData" 1 "Values" "Custom"
ExternalData */Facility/f1 SetInputUnit "LinearData" "Values" ""

The following examples create and fill a data group that contains character data:

ExternalData */Satellite/Satellite1 AddGroup "Test Char Data" 3 Fuel Mass Name Char Spin Rate
ExternalData */Satellite/Satellite1 AddData "Test Char Data" "27 Oct 2004 00:00:00.00" 303.25 "Name 1" 4.2938
ExternalData */Satellite/Satellite1 AddData "Test Char Data" "27 Oct 2004 00:02:17.33" 312.02 "String at 2:17.33" 4.6789

Return message

Group membership

This command belongs to the following group(s):

Area Targets





Facilities, Places & Targets



Stars & Planets