
 Usage

vtkInterpolatedVelocityField acts as a continuous velocity
field via cell interpolation on a vtkDataSet,
NumberOfIndependentVariables = 4 (x,y,z,t) and
NumberOfFunctions = 3 (u,v,w). As a concrete sub-class of
vtkAbstractInterpolatedVelocityField, this class adopts two
levels of cell caching for faster though less robust cell
location than its sibling class
vtkCellLocatorInterpolatedVelocityField. Level #0 begins
with intra-cell caching. Specifically, if the previous cell
is valid and the nex point is still within it, ( vtkCell::
EvaluatePosition() returns 1, coupled with the new
parametric coordinates and weights ), the function values
are interpolated and vtkCell::EvaluatePosition() is invoked
only. If it fails, level #1 follows by inter-cell location
of the target cell (that contains the next point). By inter-
cell, the previous cell gives an important clue / guess or
serves as an immediate neighbor to aid in the location of
the target cell (as is typically the case with integrating a
streamline across cells) by means of vtkDataSet:: FindCell
(). If this still fails, a global cell search is invoked via
vtkDataSet::FindCell().
Regardless of inter-cell or global search, vtkPointLocator
is employed as a crucial tool underlying the cell locator.
The use of vtkPointLocator casues
vtkInterpolatedVelocityField to return false target cells
for datasets defined on complex grids.
To create an instance of class vtkInterpolatedVelocityField,
simply invoke its constructor as follows

    obj = vtkInterpolatedVelocityField



 Methods

The class vtkInterpolatedVelocityField has several methods
that can be used. They are listed below. Note that the
documentation is translated automatically from the VTK
sources, and may not be completely intelligible. When in
doubt, consult the VTK website. In the methods listed below,
obj is an instance of the vtkInterpolatedVelocityField
class.

* string = obj.GetClassName ()
* int = obj.IsA (string name)
* vtkInterpolatedVelocityField = obj.NewInstance ()
* vtkInterpolatedVelocityField = obj.SafeDownCast (vtkObject
  o)
* obj.AddDataSet (vtkDataSet dataset) - Add a dataset used
  for the implicit function evaluation. If more than one
  dataset is added, the evaluation point is searched in all
  until a match is found. THIS FUNCTION DOES NOT CHANGE THE
  REFERENCE COUNT OF DATASET FOR THREAD SAFETY REASONS.
* int = obj.FunctionValues (double x, double f) - Evaluate
  the velocity field f at point (x, y, z).
* obj.SetLastCellId (vtkIdType c, int dataindex) - Set the
  cell id cached by the last evaluation within a specified
  dataset.
* obj.SetLastCellId (vtkIdType c)


* FreeMat_Documentation
* Visualization_Toolkit_Filtering_Classes
* Generated on Thu Jul 25 2013 17:18:31 for FreeMat by
  doxygen_ 1.8.1.1

