problem with VTK output

[einatlev]

Hello
For some reason, some of my models output VTK files that have small "mutations". For example, a few extra lines of zeros instead of the actual values. Also I sometimes get an error from Paraview saying that the number of data points doesn't match the declaration. The values in the output .dat file are correct. For example, for the same run:


in output.dat:

Code: Select all

viscosity
Perm: NULL
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     
   500000.00000000000     

While in output.vtk:

Code: Select all

SCALARS Viscosity double
LOOKUP_TABLE default
  5.0000000E+005
  0.0000000E+000
  0.0000000E+000
  0.0000000E+000
  0.0000000E+000
  0.0000000E+000
  0.0000000E+000
  0.0000000E+000
  0.0000000E+000
  0.0000000E+000
  0.0000000E+000

Why is this happening? how can it be fixed?
I'm running Elmer 6.1 on Ubunto

[einatlev]

Upon further investigation, it appears that the output.dat file doesn't contain the same number of entries as the number of mesh nodes in the Pressure/Temperature/Viscosity point data sections... It contains much less -- 110021 entries instead of 110485 -- as I suppose is suggested by the line:

Perm: 110485 110021

at the top of the velocity section in output.dat

Why is there not a 1-to-1 correlation? what is this permutation anyhow? how do I avoid it?

Thanks!

[raback]

Hi

I suggest always using VTU output. VTK is obsolite, at least for Paraview.

The permutation tells what is the dof index in given nodal index. There are two uses for it:
1) A non-zero entry tells that the dof is active in the node.
2) The permutation may be used to minimize the bandwidth of the resulting linear system.

-Peter