[Paraview] calculator tensor field

[Marschmann at stud.uni-heidelberg.de]

Hello everyone,

I have three displacement field vector components u, v, w in my .vtk file
and wish to display the associated stress tensor.
I made the following steps:

- Apply the filter Gradient Of Unstructued DataSet
-> Now have 9 scalars Gradient_0, ... , Gradient 8

- compute components of stress tensor via sigma_ij = div(Gradient) + u_i,j
-> Now have additional 9 scalars sigma_ij

- from this form traction vectors:
T_i = sigma_ij e_j   ,where e_j are the unit vectors iHat

-> Now have three traction vectors from which the tensor field  
computation doesnt work:

- I do Result = T_1*iHat + T_2*jHat + T_3*kHat for the tensor  
calculation and get the following error message:

ERROR: In  
/home/abuild/rpmbuild/BUILD/ParaView-v4.0.1-source/VTK/Common/Misc/vtkFunctionParser.cxx, line  
201
vtkFunctionParser (0x205ddac0): Parse: Error deciding between  
ambiguous operators


ERROR: In  
/home/abuild/rpmbuild/BUILD/ParaView-v4.0.1-source/VTK/Common/Misc/vtkFunctionParser.cxx, line  
300
vtkFunctionParser (0x205ddac0): expecting either 2 scalars or a scalar  
and a vector


ERROR: In  
/home/abuild/rpmbuild/BUILD/ParaView-v4.0.1-source/VTK/Common/Misc/vtkFunctionParser.cxx, line  
201
vtkFunctionParser (0x205ddac0): Parse: Error deciding between  
ambiguous operators


- Can you help me or tell me gow to visualize the stress tensor from  
the displacement field?
- Alternatively you it would also be good to know how to multiply the  
result of  filter Gradient of Unstructured DataSet by a scalar value.


Many thanks for helping!
Gianna