[Paraview] [EXTERNAL] Warp by scalar for CELL_DATA

[Magician]

Hi Mohammad,


Sorry for late my reply.
There is an easy example:
> # vtk DataFile Version 2.0
> QuadCell
> ASCII
> DATASET UNSTRUCTURED_GRID
> POINTS 9 FLOAT
> 0 0 0
> 0.4 0 0
> 1 0 0
> 0 0.25 0
> 0.4 0.25 0
> 1 0.25 0
> 0 1 0
> 0.4 1 0
> 1 1 0
> CELLS 4 20
> 4 0 1 4 3
> 4 1 2 5 4
> 4 3 4 7 6
> 4 4 5 8 7
> CELL_TYPES 4
> 9 9 9 9
> CELL_DATA 4
> SCALARS scalar FLOAT 1
> LOOKUP_TABLE DEFAULT
> 1.0
> 2.0
> 4.0
> 8.0


This source includes 4 Quad cells and Cell-based Scalar values.
These cells' area values are different.

If you apply "Cell Data to Point Data" filter, the ID:4 point's
value is calculated as 3.75 {= (1.0 + 2.0 + 4.0 + 8.0) / 4.0}.


Magician


On 2012/07/18, at 7:56, Mohammad Mirzadeh wrote:

> Hi Magician,
> 
> Thanks for the information. Could you please let me know of your source? 
> 
> Thanks,
> Mohammad
> 
> On Tue, Jul 17, 2012 at 3:21 PM, Magician <f_magician at mac.com> wrote:
> Hi Mohammad,
> 
> 
> According to my research, Cell Data to Point Data is just calculating
> averages of surrounding cells.
> 
> I think it's not proper to explain the function as 'interpolation'.
> Also I hope it will be adapted to geometric interpolation method.
> 
> 
> Magician
> 
> 
> > Thanks that might work. Just another question. What type of interpolation
> > does PV use to map cell data information to point data? Obviously there are
> > more nodes than cells ... is it using some sort of least-square method?
> >
> > On Tue, Jul 17, 2012 at 12:36 AM, Felipe Bordeu
> > <felipe.bordeu at ec-nantes.fr>wrote:
> >
> >> hi, you can use the shrink filter with a shrink factor of 0.99999 to get
> >> disconnected nodes. the you can apply the warp filter.
> >>
> >> Felipe
> >>
> >> Le 17/07/2012 03:09, Mohammad Mirzadeh a ?crit :
> >>
> >> Yeah I did that. Problem is, cell_data variables are discontinuous at some
> >> points and I fear interpolation will introduce unnecessary oscillations ...
> >>
> >> On Mon, Jul 16, 2012 at 6:03 PM, Scott, W Alan <wascott at sandia.gov> wrote:
> >>
> >>> Could you just run Point Data to Cell Data, then the Warp by scalar
> >>> filter?
> >>>
> >>>
> >>>
> >>> Alan
> >>>
> >>>
> >>>
> >>> *From:* paraview-bounces at paraview.org [mailto:
> >>> paraview-bounces at paraview.org] *On Behalf Of *Mohammad Mirzadeh
> >>> *Sent:* Monday, July 16, 2012 6:52 PM
> >>> *To:* paraview at paraview.org
> >>> *Subject:* [EXTERNAL] [Paraview] Warp by scalar for CELL_DATA
> >>>
> >>>
> >>>
> >>> Is there a filter similar to warp by scalar but for CELL_DATA variables?