CFD Online Discussion Forums - [General] Python script to sum up a variable for all cells

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):

Code:

# 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