[Paraview] Sorting the data from GetInputDataObject in ProgrammableFilter

[Laurent Paul]

Hi all,

I use the programmable filter to do some basic computations (Axis, mean 
point etc...).
I often need to access to more than one data as input, so I use 
GetInputDataObject(0,x), x being the input number. Let's say that all 
inputs are vtkPointSource.
I don't understand how the sorting is done. If I select 4 vtkPointSource 
from the object list, I get the coordinates, but in a random order. It 
seems there is no logical sorting such as object number in the object 
list or selection order using the ctrl+click.
I'm sure there is a hidden logical sorting...
How can I get correctly sorted inputs, for example according to the 
object list?

Thanks,
Laurent.