[vtkusers] retrieve data from vtkUnstructuredGrid

[Pascal Seng]

Hello! Everybody,

This question is for people who masters vtk:
With a vtkUnstructuredGrid ,which contains a lot of attributes(for 
example, that structure can contain the points coordinates and for each 
point, there is a potential and other data), how can I retrieve all that 
information for a specific vertex?

Thanks a lot for answers.
Pascal Seng.