[vtkusers] vtkCellDerivatives - Example and usage

[Stefan Gutschling]

hello vtkusers,

I am looking for a small example (tcl od cxx) that uses the
vtkCellDerivatives
class from the contrib directory in vtk3.12. 

unfortunately, the example cellDerivs.tcl needs the vtk-dataset 
"cylFlow.vtk", that is not within the vtk20Data.part*.tar.gz
and MissingData.tar.gz files. 

I like to calculate the derivatives of electric potentials
given at nodes of a FEM mesh and display them.

Sofar I created a small program that reads in my data
Nodes, electric potentials (at the FEM nodes), the elements
(triangles saved by node ids )

For this I used the following classes:

  vtkPolyData *mesh = vtkPolyData::New();
  vtkPoints *nodeCoords=vtkPoints::New();
  vtkScalars *=vtkScalars::New();
  vtkCellArray *cells=vtkCellArray::New();

 # ...with some code in between I
 # assign the points(nodes of mesh) and scalar values (at nodes)
 # in "nodeCoords" and "nodeScalars"
 # also I created all triangular elements of the mesh stored in "cells"

 # then add all to the polydata

  mesh->SetPoints(nodeCoords);
  nodeCoords->Delete();

  // assign cells to mesh
  mesh->SetPolys(cells);
  cells->Delete();

  // assign potentials to mesh 
  mesh->GetPointData()->SetScalars(nodeScalars);
  nodeScalars->Delete();

  # after that follows the Mapper,Actor, add the actor to
  # the renderer etc...

How do I have to use the vtkCellDerivatives class for my
problem...?


Best Regards,

stevie  

-- 
----------------------------------------------------------------
Dr. Stefan Gutschling
EPCOS AG  
Surface Acoustic Wave Components Division  
OFW E NT
Tel.: ++49 89-636-21936
Fax.: ++49 89-636-27304
mailto:Stefan.Gutschling at epcos.com
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