Description

Transforms the input vector from this axes into the output axes.

Syntax

[Visual Basic .NET]
Public Function Transform( _ ByVal Epoch As System.Object, _ ByVal OutputAxes As IAgCrdnAxes, _ ByVal VectorInMyAxes As IAgCartesian3Vector _ ) As IAgCrdnAxesTransformResult

[Visual Basic .NET]

Public Function Transform( _
   ByVal Epoch As System.Object, _
   ByVal OutputAxes As IAgCrdnAxes, _
   ByVal VectorInMyAxes As IAgCartesian3Vector _
) As IAgCrdnAxesTransformResult

[C#]
public IAgCrdnAxesTransformResult Transform( System.Object Epoch, IAgCrdnAxes OutputAxes, IAgCartesian3Vector VectorInMyAxes );

[C#]

public IAgCrdnAxesTransformResult Transform(
   System.Object Epoch, 
   IAgCrdnAxes OutputAxes, 
   IAgCartesian3Vector VectorInMyAxes
);

[Managed C++]
public: IAgCrdnAxesTransformResult^ Transform( VARIANT Epoch, IAgCrdnAxes ^ OutputAxes, IAgCartesian3Vector ^ VectorInMyAxes );

[Managed C++]

public: IAgCrdnAxesTransformResult^ Transform(
   VARIANT Epoch, 
   IAgCrdnAxes ^ OutputAxes, 
   IAgCartesian3Vector ^ VectorInMyAxes
);

[Java]
public IAgCrdnAxesTransformResult transform( Variant Epoch, IAgCrdnAxes OutputAxes, IAgCartesian3Vector VectorInMyAxes );

[Java]

public IAgCrdnAxesTransformResult transform(
   Variant Epoch, 
   IAgCrdnAxes OutputAxes, 
   IAgCartesian3Vector VectorInMyAxes
);

[Unmanaged C++]
public: HRESULT Transform( VARIANT Epoch, IAgCrdnAxes * OutputAxes, IAgCartesian3Vector * VectorInMyAxes, IAgCrdnAxesTransformResult ** ReturnValue );

[Unmanaged C++]

public: HRESULT Transform(
   VARIANT Epoch, 
   IAgCrdnAxes * OutputAxes, 
   IAgCartesian3Vector * VectorInMyAxes, 
   IAgCrdnAxesTransformResult ** ReturnValue
);

Parameters

Epoch: Specify an epoch. The method may throw an exception if the epoch parameter specified cannot be converted to a currently selected date unit.
OutputAxes: Specify an axes the input vector is transformed into.
VectorInMyAxes: Specify an input vector to be transformed from this axes into the ouput axes.

Remarks

Consider a vector rotating and changing its magnitude in space. The vector's direction and magnitude as well as its time rate of change can be given at some specified time using Cartesian coordinates in one of VGT coordinate axes. The same vector at the same time will have different Cartesian coordinates with respect to different VGT coordinate axes. One set of coordinates can be obtained from the other using Transform methods defined for VGT coordinate axes: given time and coordinates with respect to one VGT coordinate axes, these methods output coordinates with respect to other axes. For example, consider a position vector of a satellite defined as displacement vector between the center of the Earth and the center of the satellite. When this position vector is viewed with respect to the Moon fixed axes, its magnitude remains the same because the vector is still a displacement vector between the Earth center and the center of satellite. Its Cartesian coordinates with respect to the Moon fixed axes will be different but not its magnitude.

Example

Transform a vector to the Earth's Fixed axes.

[C#] Copy Code

// Get the satellite's ICRF cartesian position at 180 EpSec using the data provider interface 

int numEpSec = 180; 

IAgDataProviderGroup dpGroup = sat.DataProviders["Cartesian Position"] as IAgDataProviderGroup; 

Array elements = new object[] { "x", "y", "z" }; 

IAgDataPrvTimeVar dp = dpGroup.Group["ICRF"] as IAgDataPrvTimeVar; 

IAgDrResult dpResult = dp.ExecElements(numEpSec, numEpSec, 60, ref elements); 

double xICRF = (double)dpResult.DataSets[0].GetValues().GetValue(0); 

double yICRF = (double)dpResult.DataSets[1].GetValues().GetValue(0); 

double zICRF = (double)dpResult.DataSets[2].GetValues().GetValue(0); 

 

// Create a vector using the ICRF coordinates 

IAgCrdnAxes axesICRF = sat.Vgt.WellKnownAxes.Earth.ICRF; 

IAgCartesian3Vector vectorICRF = Application.ConversionUtility.NewCartesian3Vector(); 

vectorICRF.Set(xICRF, yICRF, zICRF); 

 

// Use the Transform method to transform ICRF to Fixed 

IAgCrdnAxes axesFixed = sat.Vgt.WellKnownAxes.Earth.Fixed; 

IAgCrdnAxesTransformResult result = axesICRF.Transform(numEpSec, axesFixed, vectorICRF); 

 

// Get the Fixed coordinates 

double xFixed = result.Vector.X; 

double yFixed = result.Vector.Y; 

double zFixed = result.Vector.Z;