Nearest Neighbour Averaging

ParaView Support
4

Here is an example using the programmable filter as Cory suggested :

  • Create some dummy input with celldata
    • Source > Unstructured Cells Types
    • Filters > PointToCellData
  • Create programmable filter with the following script. We will average the “DistanceToCenter” array
import numpy as np 
input0 = inputs[0]
num = input0.GetNumberOfCells()

Array = np.zeros(num, dtype=np.float64)
ptIds = vtk.vtkIdList()
cellIds = vtk.vtkIdList()
otherCells = vtk.vtkIdList()


for i in range(num):
       input0.GetCellPoints(i,ptIds)
       # Get all cells attached to the first point
       input0.GetPointCells(ptIds.GetId(0),cellIds)
       # similarly for all other points
       for j in range(1,ptIds.GetNumberOfIds()):
           input0.GetPointCells(ptIds.GetId(j),otherCells)
           # merge results
           for k in range(otherCells.GetNumberOfIds()):
               cellIds.InsertUniqueId(otherCells.GetId(k))
       # remove current cell
       cellIds.DeleteId(i)
       # average results
       for k in range(cellIds.GetNumberOfIds()):
           Array[i] += input0.CellData["DistanceToCenter"][cellIds.GetId(k)]
       Array[i] /= cellIds.GetNumberOfIds()

         

output.CellData.append(Array, "A")