•  

ComputeDerivatives Method

Returns the vectors describing the edge at the specified parameter.

Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0)

Syntax

C# 
public Transform ComputeDerivatives(
	double parameter
)
Visual Basic 
Public Function ComputeDerivatives ( _
	parameter As Double _
) As Transform
Visual C++ 
public:
Transform^ ComputeDerivatives(
	double parameter
)

Parameters

parameter
Type: System Double
The parameter to be evaluated.

Return Value

The transformation containing a tangent vector, derivative of tangent vector, and bi-normal vector.

Remarks

The following is the meaning of the transformation members:
  • Origin is the point on the edge (equivalent to Evaluate);
  • BasisX is the tangent vector (the first derivative);
  • BasisY is the second derivative;
  • BasisZ is the bi-normal vector (tangent x normal).
Normal and bi-normal are zero if the edge is straight at the point. None of the vectors are normalized.

See Also