[hconel]

Hello,
I am trying to write a Python script to use in Paraview, where I need:
( component of a vector field ) * ( cell volume )
summed up for all cells in the domain. I have no clue where to start and couldn't find a similar script. Can someone give me an idea for this?
Thanks in advance.

[tkarabela]

Hi, you can use the Calculator to make a new variable from your vector field and then use the Integrate filter to compute the sum. Here is the example in Python (using Paraview 5.6, but it should work in earlier versions too):

# Load your case and extract the domain - this will be specific for your case.
# The example below is suitable for OpenFOAM case exported using foamToEnsight.
from paraview.simple import *
case = EnSightReader(CaseFileName="my-ensight-data.case")
Show(case)
domain = ExtractBlock(case)
domain.BlockIndices = [1]
Show(domain)

# If you have data in nodes, interpolate to cells first,
# otherwise skip this step.
domain = PointDatatoCellData(domain)

# Extract the vector component to scalar
# (here my variable is "U", replace it with your variable name).
calc = Calculator(domain)
calc.AttributeType = "Cell Data"
calc.Function = "U_X"

# Integrate over domain.
integrate = IntegrateVariables(calc)
result = integrate.GetCellDataInformation().GetArray("Result").GetRange()[0]
print "Summed value is", result