Errase Points of a VTU. Get coordinates/scalar field values of CP

Hi Paraview Experts

I am working to get the critical points of a scalar field. I want to erase/filter unnecessary critical points, How can it do?

another question

how get the coordinates and value of the scalar field of the critical points from a vtu file?

I share some file:

rho_cubane.vti: scalar field
CP1.vtu: field with critical points script pvpython
cp1.png: image with critical points and scalar field. I want to eliminate the points far away of scalar field and get the coordinates and scalar field value for the other

CP1.vtu (783.6 KB) (712 Bytes)
rho_cubane.vti (2.4 MB)