getting at geometry point data within a python macro

How do you read or modify geometry point data within a python macro?

I’m reading in an STL file with STLReader (that works ok)

Then I’m using pd = reader.GetPointDataInformation()

but its not working, and there are no error messages.

you should not attempt to modify geometry point data in your python macro, as the data is located on the server while your macro runs on the client.

What are you trying to achieve exactly ?

Trying to get the STL point data, to either modify it (eg morphing) or add new geometry (eg fill holes) or maybe delete geometry… Can it be done with the macro capability or maybe there is a better approach?

You should use Python Programmable Filter for that:
https://www.paraview.org/Wiki/Python_Programmable_Filter

Got it sorted eventually - thanks very much for the support !

ended up using python macro commands such as these to achieve the task:
data = paraview.servermanager.Fetch(reader)
pt = data.GetPoint(j) # for point coordinates
p1 = data.GetCell(j).GetPointId(0) # for connectivity

Keep in mind that Fetch can be expansive when working remotely and that it does not allow you to modify the data and visualize it in ParaView, only to inspect the data manually.