[JMuskat]

Hello,

I'm looking for an answer regarding how--theoretically/code-based--ParaView (currently using v5.6.0) calculates the gradient on an unstructured dataset. I have a volume mesh filled with velocity data from my ANSYS Fluent CFD simulation; I use my scalar array/vector for CFD velocities and get the gradient from using "GradientOfUnstructuredDataSet" within ParaView.

Note that a gradient's calculation can change order of accuracy by including a higher order polynomial/function for estimating. I've tried looking for the source code and all over the forums, but I've come up with nothing. If you are able to point me towards this specific filter's source code OR explain how ParaView numerically solves for the unstructured gradient, I would be extremely appreciative. It appears that ParaView will do what I want (eventually get Wall Shear Stress), but I need to be able to argue what order of accuracy/understand exactly what is going on with this calculation.