[Paraview] [EXTERNAL] Idiot's Guide to Programmable Filter

Wed Apr 29 11:01:12 EDT 2015

Berk,

Thanks for your reply.

I am using Paraview 4.3, so hopefully that has the improvements you mentioned.

I guess if I could figure out what objects are used for Blocks in side the Programmable filter I could do more on my own, but it’s clear they are different from in a python script, but still not clear what they are.

So a typical application would be a special version of point data to cell data.

I have some node variables.     I want to find all the nodes attached to each element, do some calculations on those node variables to generate a new element variable.   So basically like

Loop over blocks
     Loop over elements in block
                Find all nodes connected to element
                Perform calculations based on node variables
                Assign new element variable(s) based on calculations

Thanks for any insight – Alan at Sandia has suggested I check the latest user guide, and I will, but I haven’t seen a good element example for the Programmable filter yet – I don’t have any problem doing nodal manipulations, but I have a good example of that.

Dennis

From: Berk Geveci [mailto:berk.geveci at kitware.com]
Sent: Wednesday, April 29, 2015 10:29 AM
To: Scott, W Alan
Cc: Dennis Conklin; paraview at paraview.org
Subject: Re: [Paraview] [EXTERNAL] Idiot's Guide to Programmable Filter

Hey Dennis,

Which version of ParaView are you using? We have made some significant improvements to the way we handle multi-block datasets (which Exodus produces) in the latest version.

The interface in the Programmable Filter is somewhat different than what you would have in a ParaView Python script. This is because you actually have access to the full data and the objects in there are of different types.

If you give me some examples of what you are trying to do in the programmable filter, I can provide code that demonstrates the use of the API in the programmable filter.

Best,
-berk

On Tue, Apr 28, 2015 at 10:32 PM, Scott, W Alan <wascott at sandia.gov<mailto:wascott at sandia.gov>> wrote:
Dennis,
The Python/ Programmable filter is a black box to me (i.e., I won’t be much additional help).  However, the place i would start would be the new, super-duper ParaView Guide.  Kitware – and especially Utkarsh – have done a great job on it.

Rather than giving the link, here is how to find it.  It is sold in paper form on Amazon, and also is available as a .pdf for free (lacking 3 chapters, not related to the python filter).

paraview.org/<http://paraview.org/> Resources/ ParaView Guide.  This includes the link to the .pdf.  You are interested in (at least) chapter 13.  It is listed under master section II, Reference Manual.

Alan

From: ParaView [mailto:paraview-bounces at paraview.org<mailto:paraview-bounces at paraview.org>] On Behalf Of Dennis Conklin
Sent: Tuesday, April 28, 2015 11:11 AM
To: paraview at paraview.org<mailto:paraview at paraview.org>
Subject: [EXTERNAL] [Paraview] Idiot's Guide to Programmable Filter

All,

I’m a little confused by what objects are inside a programmable filter.    I have a multi-block EXODUS dataset.    When I read this in it is a Exodus2Reader object (sp?) and I can access the blocks, pointdata, celldata, etc in a python script.

Once I get inside the Programmable filter, the  blocks of the input[] seem to have different member functions than they did in a Python script.   So I can’t figure out  how to get connectivity,   number of cells in a block, generate new cell variables, etc.

So, if I’m in a Programmable Filter, what object do I look at in either the Paraview or VTK class libraries to understand what the properties of the block are?

Thanks very much for any insight you can give.

Dennis

_______________________________________________
Powered by www.kitware.com<http://www.kitware.com>

Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html

Please keep messages on-topic and check the ParaView Wiki at: http://paraview.org/Wiki/ParaView

Search the list archives at: http://markmail.org/search/?q=ParaView

Follow this link to subscribe/unsubscribe:
http://public.kitware.com/mailman/listinfo/paraview

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/paraview/attachments/20150429/4267c977/attachment.html>