[Samarth_2412]

Hi Users!
This might be really silly question as I'm new to using openFOAM and paraiew, but I have been trying to make an eigenvalue plot in the domain of flow.

I have been trying to perform an instability analysis and have been successful in establishing the base flow and also have managed to successfully compile and run a modified version of the icoFoam solver (modified to handle the Linearized Navier-Stokes Equation)

In my searches, I came across suggestions that I should use the python calculator for this purpose with the expression "eigenvalue(U)", but when i attempt to do so, I get the message-
"RuntimeError: eigenvalue only works for an array of matrices(3D array). input shape(15521,3)"

How can I resolve this error? In all my searches, i came across a few suggestions but not how to resolve this error. I would be extremely grateful if i could be pointed in the right direction!
PS- I'm running paraview version 5.6.0

Thanks a lot!