Visualise the errors as relative to the magnitude of the deformation

I have two volumetric liver meshes in .vtk format (i.e. ground-truth and predicted versions) and I want to visualise the errors as relative to the magnitude of the deformation. eg a percentage error. Is it possible in Paraview ? If so can you elaborate the steps with an example please ?

I have herewith attached two samples .vtk files for your further reference. (80.7 KB)

It looks like your ground truth and prediction meshes have the same topology. That is, they have the same points and the same cells defined in the same order. That’s good because you can use the Append Attributes filter to combine data from the two models.

The first step is to use the Calculator filter to convert the point coordinates to a field. Run Calculator on the ground truth. Set the Result Array Name to something like ground_truth and the expression to coords. Do the same for the prediction except make the Result Array Name something different like prediction.

Next, select both Calculator filters in the Pipeline Browser and add the Append Attributes filter. This will create a new mesh with both ground_truth and prediction.

Finally make a third Calculator filter that subtracts the prediction and ground_truth vectors.

Here is a state file to do this with the data you gave:
liver_deform.pvsm (767.0 KB)