Saving solution (magnetostatics) to .vtk - extremely large files

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1

Hello,

i’d like to save my solution of the ngsolve calculation to a .vtk file to prepare some nice graphics with ParaView. The problem is a magnetostatic one and has about 600.000 elements.
The export is lasting forever and producing extremely large files. (way over 20 GB)

i use the following code:

[code]# VTKOutput object
vtk = VTKOutput(ma=mesh,
coefs=[u],
names = [“vectorfield”],
filename=“result”,
subdivision=3)

Exporting the results:

vtk.Do()[/code]

Is there something wrong with the concept of exporting the solution?
Can i reduce the resolution of the numbers?

Many thanks in advance for your support!
With best regards

2

Hi creativeworker,

The VTK-legacy format (what is used here) is really consuming a lot of disk space (we haven’t implemented the VTK binary format which would spare a lot of space). Your example snippet is fine. However, you are using subdivision=3 which means that every tetrahedron is divided into 8³=512 tetrahedron only for the purpose of visualization. This makes sense for higher order polynomials representing solutions with large variations. However, if you are ok with a low resolution visualization, try subdivision=0 which should give you roughly a file size of around 40 MB.

Best,
Christoph

3

Thank you! This solved it for my purpose. I wasn’t aware of the extreme effect of the subdivision parameter. FYI: The file has now 160MB.