[Paraview] Question about Integrate Variables Filter

[Magician]

Hi all,


Now I found a bug of the filter.

My ParaView's version is 3.14.1.
I define node names as below:
> c--d
> |  |
> a--b

Case 1: a=1.0, b=0.0, c=0.0, d=0.0
Integration Value = 0.33333

Case 2: a=0.0, b=1.0, c=0.0, d=0.0
Integration Value = 0.16666

Case 3: a=0.0, b=0.0, c=1.0, d=0.0
Integration Value = 0.16666

Case 4: a=0.0, b=0.0, c=0.0, d=1.0
Integration Value = 0.33333

So Integration Values are calculated as (2*a+b+c+2*d)/6.
I think it's not a good result.


Magician


On 2012/06/08, at 12:54, Magician wrote:

> Hi all,
> 
> 
> I'm now comparing integration results of each postprocessors.
> I made a simple Quadratic VTK model as below:
>> # vtk DataFile Version 2.0
> 
>> QuadCell
>> ASCII
>> DATASET UNSTRUCTURED_GRID
>> POINTS 4 FLOAT
>> 0 0 0
>> 1 0 0
>> 0 1 0
>> 1 1 0
>> CELLS 1 5
>> 4 0 1 3 2
>> CELL_TYPES 1
>> 9
>> POINT_DATA 4
>> SCALARS scalar FLOAT 1
>> LOOKUP_TABLE DEFAULT
>> 0.0
>> 1.0
>> 2.0
>> 4.0
> 
> When I apply Point Data to Cell Data filter,
> scalar values are interpolated as 1.75.
> It may be calculated as (0.0+1.0+2.0+4.0)/4.0.
> 
> But when I apply Integrate Variables filter,
> scalar value is integrated as 1.833....
> The area value of quadratic cell is 1.0, so I thought
> integrated values should be equal to cell data.
> 
> How the integrated value is calculated?
> 
> 
> Magician