# In Situ Support

**URL:** https://discourse.paraview.org/c/in-situ-support/8.md

[Latest](https://discourse.paraview.org/latest.md) · [Categories](https://discourse.paraview.org/categories.md) · [Tags](https://discourse.paraview.org/tags.md)

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## [About the In Situ Support category](https://discourse.paraview.org/t/about-the-in-situ-support-category/27)

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**Author:** [@cory.quammen](https://discourse.paraview.org/u/cory.quammen)\
**Replies:** 4\
**Last updated:** [November 29, 2018, 7:07pm UTC](https://discourse.paraview.org/t/about-the-in-situ-support-category/27 "2018-11-29T19:07:18Z")

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A place for questions about in situ visualization with ParaView including ParaView Catalyst.

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## [ParaView 6.2.0-RC1 throws errors for non unique nodes](https://discourse.paraview.org/t/paraview-6-2-0-rc1-throws-errors-for-non-unique-nodes/17668)

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**Author:** [@Alexandre\_Minot](https://discourse.paraview.org/u/Alexandre_Minot)\
**Replies:** 10\
**Last updated:** [September 9, 2026, 1:16pm UTC](https://discourse.paraview.org/t/paraview-6-2-0-rc1-throws-errors-for-non-unique-nodes/17668 "2026-09-09T13:16:41Z")

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Hello, I am getting this error while testing ParaView 6.2.0-RC1: ( 2.503s) \[pvbatch \] vtkDataAssembly.cxx:591 ERR| vtkDataAssembly (0x7c87cc2a7f40): A child node with name 'SIDEWALL' already exists unde…

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## [Implementing Catalyst in the OVERFLOW solver](https://discourse.paraview.org/t/implementing-catalyst-in-the-overflow-solver/17673)

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**Author:** [@Darby\_Vicker](https://discourse.paraview.org/u/Darby_Vicker)\
**Replies:** 2\
**Last updated:** [August 6, 2026, 12:55pm UTC](https://discourse.paraview.org/t/implementing-catalyst-in-the-overflow-solver/17673 "2026-08-06T12:55:16Z")

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Hello, I’m interested in implementing catalyst in the OVERFLOW solver. If anyone has pointers for implementing this in a structured solver written in FORTRAN, please let me know. To get started, I’m working my way th…

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## [Debugging segfault while passing data to Catalyst 2.1](https://discourse.paraview.org/t/debugging-segfault-while-passing-data-to-catalyst-2-1/17666)

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**Author:** [@paulmelis](https://discourse.paraview.org/u/paulmelis)\
**Replies:** 2\
**Last updated:** [July 24, 2026, 2:34pm UTC](https://discourse.paraview.org/t/debugging-segfault-while-passing-data-to-catalyst-2-1/17666 "2026-07-24T14:34:23Z")

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I’m passing a small 3D vector field (less than 100^3) to the Catalyst API. When the code runs single-threaded, and there is only one full grid to pass, things work without issue and the data correctly ends up in Paraview…

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## [render multiple views with single Catalyst Python script](https://discourse.paraview.org/t/render-multiple-views-with-single-catalyst-python-script/16891)

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**Author:** [@uturuncoglu](https://discourse.paraview.org/u/uturuncoglu)\
**Replies:** 2\
**Last updated:** [July 10, 2026, 2:43pm UTC](https://discourse.paraview.org/t/render-multiple-views-with-single-catalyst-python-script/16891 "2026-07-10T14:43:40Z")

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Hi, I wonder if there is a way to output all the render views with Catalyst. In my case, I have four panel but the Catalyst Python script is only processing the one of them. Of course, I could create four different scri…

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## [Corrupted refinement ratio when processing an "amrmesh" mesh in paraview-catalyst](https://discourse.paraview.org/t/corrupted-refinement-ratio-when-processing-an-amrmesh-mesh-in-paraview-catalyst/17571)

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**Author:** [@cityadmirer](https://discourse.paraview.org/u/cityadmirer)\
**Replies:** 5\
**Last updated:** [June 9, 2026, 2:38pm UTC](https://discourse.paraview.org/t/corrupted-refinement-ratio-when-processing-an-amrmesh-mesh-in-paraview-catalyst/17571 "2026-06-09T14:38:21Z")

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Overview I’m working on some CFD code based on the AMReX library. It provides utilities to map a uniform Catersian AMR mesh to a conduit::Node object based on the nestsets blueprint. However, when the data is processed b…

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## [Trying to understand Catalyst (Live) design choices](https://discourse.paraview.org/t/trying-to-understand-catalyst-live-design-choices/17597)

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**Author:** [@paulmelis](https://discourse.paraview.org/u/paulmelis)\
**Replies:** 7\
**Last updated:** [June 9, 2026, 12:34pm UTC](https://discourse.paraview.org/t/trying-to-understand-catalyst-live-design-choices/17597 "2026-06-09T12:34:49Z")

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I’ve been looking closer into Catalyst 2 and have some questions on why particular things are the way they are. If there’s misconceptions on my end then I apologize (and am happy to be corrected). To do live visualizat…

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## [Initializing a new pipeline during a run with ParaView Catalyst](https://discourse.paraview.org/t/initializing-a-new-pipeline-during-a-run-with-paraview-catalyst/17550)

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**Author:** [@Alexandre\_Minot](https://discourse.paraview.org/u/Alexandre_Minot)\
**Replies:** 7\
**Last updated:** [May 26, 2026, 7:16pm UTC](https://discourse.paraview.org/t/initializing-a-new-pipeline-during-a-run-with-paraview-catalyst/17550 "2026-05-26T19:16:04Z")

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Dear all, As far as I can tell, we cannot initialize a new Catalyst pipeline during a run. catalyst\_initialize() can only be called once, and that’s the place where we tell ParaView about our scripts. It would be usefu…

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## [ParaView Catalyst warns instead of raising an error when the script is not found](https://discourse.paraview.org/t/paraview-catalyst-warns-instead-of-raising-an-error-when-the-script-is-not-found/17543)

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**Author:** [@Alexandre\_Minot](https://discourse.paraview.org/u/Alexandre_Minot)\
**Replies:** 3\
**Last updated:** [May 4, 2026, 12:53pm UTC](https://discourse.paraview.org/t/paraview-catalyst-warns-instead-of-raising-an-error-when-the-script-is-not-found/17543 "2026-05-04T12:53:28Z")

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Dear all, If the catalyst script is not found, ParaView displays \[pvbatch.0 \]vtkInSituInitialization:295 WARN| File/path does not exist and not in PYTHONPATH: 'my\_paraview\_interface'. Skipping. and the ParaVie…

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## [Can Catalyst stream simulation data to multiple independent pvserver ?](https://discourse.paraview.org/t/can-catalyst-stream-simulation-data-to-multiple-independent-pvserver/17471)

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**Author:** [@Ayyoub\_Boulahri](https://discourse.paraview.org/u/Ayyoub_Boulahri)\
**Replies:** 6\
**Last updated:** [March 12, 2026, 1:54pm UTC](https://discourse.paraview.org/t/can-catalyst-stream-simulation-data-to-multiple-independent-pvserver/17471 "2026-03-12T13:54:29Z")

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I am working on an in-situ visualization pipeline using AdiosReplay/Catalyst2 and ParaView. My setup involves a running simulation that streams data via ADIOS2/SST to AdiosReplay, which then uses Catalyst to forward the …

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## [Information is out of date when using get\_execute\_params() inside a python trigger for extractors](https://discourse.paraview.org/t/information-is-out-of-date-when-using-get-execute-params-inside-a-python-trigger-for-extractors/17412)

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**Author:** [@Alexandre\_Minot](https://discourse.paraview.org/u/Alexandre_Minot)\
**Replies:** 9\
**Last updated:** [February 20, 2026, 7:16pm UTC](https://discourse.paraview.org/t/information-is-out-of-date-when-using-get-execute-params-inside-a-python-trigger-for-extractors/17412 "2026-02-20T19:16:12Z")

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A few years ago, we implemented python triggers to ParaView Catalyst extractors. Extractors can run a piece of code that returns True or False to determine whether they should be triggered. We also implemented paraview.s…

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## [Various questions, issues, and feedback migrating from legacy Catalyst to Catalyst2.](https://discourse.paraview.org/t/various-questions-issues-and-feedback-migrating-from-legacy-catalyst-to-catalyst2/17171)

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**Author:** [@YvanFournier](https://discourse.paraview.org/u/YvanFournier)\
**Replies:** 10\
**Last updated:** [January 23, 2026, 9:39am UTC](https://discourse.paraview.org/t/various-questions-issues-and-feedback-migrating-from-legacy-catalyst-to-catalyst2/17171 "2026-01-23T09:39:00Z")

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Hello, I’ve mostly finalized the transition from legacy Catalyst to Catalyst 2 in the EDF’s code\_saturne (code-saturne.org) CFD code. Last tests I ran were based on ParaView 6.0.0-603-gad0a153f2a (In Git, commit ad0a153…

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## [Catalyst connection freezes in Jupyter](https://discourse.paraview.org/t/catalyst-connection-freezes-in-jupyter/17342)

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**Author:** [@greg](https://discourse.paraview.org/u/greg)\
**Replies:** 0\
**Last updated:** [December 2, 2025, 8:36pm UTC](https://discourse.paraview.org/t/catalyst-connection-freezes-in-jupyter/17342 "2025-12-02T20:36:41Z")

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I am trying to connect from Jupyter to a catalyst in situ simulation, but Jupyter freezes in the moment, when the in situ side connects. ( The aim of this experiment is to show some statistics, no graphics, in Jupyter fr…

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## [Catalyst V2 C++ Example: python pipeline not recognized](https://discourse.paraview.org/t/catalyst-v2-c-example-python-pipeline-not-recognized/17298)

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**Author:** [@Sam\_Austin](https://discourse.paraview.org/u/Sam_Austin)\
**Replies:** 2\
**Last updated:** [November 10, 2025, 3:19pm UTC](https://discourse.paraview.org/t/catalyst-v2-c-example-python-pipeline-not-recognized/17298 "2025-11-10T15:19:05Z")

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I’m trying to run the Catalyst V2 C++ example, but the python pipeline is not running. Here is my setup: Ubuntu 24.04 Built Paraview 6.0.1 from source (regular build, not superbuild, but with MPI and catalyst enabled) B…

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## [Paraview Binaries for Mac with Catalyst](https://discourse.paraview.org/t/paraview-binaries-for-mac-with-catalyst/17253)

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**Author:** [@rs.mm](https://discourse.paraview.org/u/rs.mm)\
**Replies:** 5\
**Last updated:** [November 2, 2025, 10:42am UTC](https://discourse.paraview.org/t/paraview-binaries-for-mac-with-catalyst/17253 "2025-11-02T10:42:46Z")

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Quick question, Do the available precompiled versions of Paraview have Catalyst enabled? My In-Situ pipeline works on the Linux version but not for Mac(arm). So far, I have tried with 5.11, 5.12, 5.13 to no success.

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## [defining nodes for 3d field](https://discourse.paraview.org/t/defining-nodes-for-3d-field/17111)

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**Author:** [@uturuncoglu](https://discourse.paraview.org/u/uturuncoglu)\
**Replies:** 3\
**Last updated:** [August 20, 2025, 9:46pm UTC](https://discourse.paraview.org/t/defining-nodes-for-3d-field/17111 "2025-08-20T21:46:14Z")

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I wonder if there is some example to define 3d field (with 2d grid) or 2d field (with mesh) under Catalyst. Base on the conduit documentation, It seems that shape, stride and offset along with the data itself needs to be…

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## [Fortran Catalyst Examples](https://discourse.paraview.org/t/fortran-catalyst-examples/16586)

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**Author:** [@jml](https://discourse.paraview.org/u/jml)\
**Replies:** 1\
**Last updated:** [June 13, 2025, 10:02am UTC](https://discourse.paraview.org/t/fortran-catalyst-examples/16586 "2025-06-13T10:02:06Z")

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Dear Developers, We use fortran simulation codes, and we would like to try Catalyst on them. I create an Apptainer container Ubuntu 24.04LTS with dependencies for compilations Then install ParaView-5.13.3-MPI-Linu…

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## [Extractors don't use a target directory](https://discourse.paraview.org/t/extractors-dont-use-a-target-directory/16795)

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**Author:** [@wascott](https://discourse.paraview.org/u/wascott)\
**Replies:** 4\
**Last updated:** [June 11, 2025, 5:18pm UTC](https://discourse.paraview.org/t/extractors-dont-use-a-target-directory/16795 "2025-06-11T17:18:19Z")

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Hi guys, Extractors/ JPGs allow a user to name output images, but I don’t see where you can select a directory. What am I missing? Thanks, Alan

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## [more information about catalyst\_status\_error\_not\_found](https://discourse.paraview.org/t/more-information-about-catalyst-status-error-not-found/16362)

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**Author:** [@uturuncoglu](https://discourse.paraview.org/u/uturuncoglu)\
**Replies:** 22\
**Last updated:** [June 7, 2025, 11:39pm UTC](https://discourse.paraview.org/t/more-information-about-catalyst-status-error-not-found/16362 "2025-06-07T23:39:36Z")

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I am trying to port my application to a different platform but when I run it the error code is returning as 3 from catalyst initialization routine. 200: catalyst debug: search path from default list: \`/work2/noaa/nems/t…

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## [NeRF with VTK](https://discourse.paraview.org/t/nerf-with-vtk/14898)

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**Author:** [@Kim\_Namhyun](https://discourse.paraview.org/u/Kim_Namhyun)\
**Replies:** 2\
**Last updated:** [June 2, 2025, 2:38pm UTC](https://discourse.paraview.org/t/nerf-with-vtk/14898 "2025-06-02T14:38:19Z")

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Hello guys. I just want to reconstruct 3d volume from screenshot of view of vtk/paraview renderer. To do it, I need to make my own transform.json file which has camera pose(camera to world) matrix and some other parame…

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## [Paraview Catalyst on Windows](https://discourse.paraview.org/t/paraview-catalyst-on-windows/15450)

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**Author:** [@gsabhishek](https://discourse.paraview.org/u/gsabhishek)\
**Replies:** 8\
**Last updated:** [May 13, 2025, 11:14am UTC](https://discourse.paraview.org/t/paraview-catalyst-on-windows/15450 "2025-05-13T11:14:23Z")

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Hi, I installed the ParaView executable (ParaView-5.13.0-MPI-Windows-Python3.10-msvc2017-AMD64.msi) on Windows. To set the path to the CATALYST\_IMPLEMENTATION\_PATHS I set it to the catalyst.dll located at “Paraview 5.13…

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## [Running catalyst on GitHub Action with Ubuntu](https://discourse.paraview.org/t/running-catalyst-on-github-action-with-ubuntu/16504)

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**Author:** [@uturuncoglu](https://discourse.paraview.org/u/uturuncoglu)\
**Replies:** 11\
**Last updated:** [April 21, 2025, 4:59pm UTC](https://discourse.paraview.org/t/running-catalyst-on-github-action-with-ubuntu/16504 "2025-04-21T16:59:45Z")

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Hi All, I am trying to add a CI/CD testing to my code that aims to run ParaView+Catalyst to create some simple visualization etc. through use of GitHub runners. I could able to install everything using spack package man…

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## [Issue with actual rendering under Catalyst](https://discourse.paraview.org/t/issue-with-actual-rendering-under-catalyst/16271)

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**Author:** [@uturuncoglu](https://discourse.paraview.org/u/uturuncoglu)\
**Replies:** 7\
**Last updated:** [March 11, 2025, 3:41pm UTC](https://discourse.paraview.org/t/issue-with-actual-rendering-under-catalyst/16271 "2025-03-11T15:41:29Z")

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Hi, I am getting error like double free or corruption (fasttop) when I try to render a very simple image with ParaView Catalyst. The trace looks like following (sorry I did not compile paraview or catalyst in debug mode…

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## [Issues with Catalyst 2.0 Installation & Failing Tests (ctest)](https://discourse.paraview.org/t/issues-with-catalyst-2-0-installation-failing-tests-ctest/16107)

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**Author:** [@Bhavesh](https://discourse.paraview.org/u/Bhavesh)\
**Replies:** 20\
**Last updated:** [March 4, 2025, 10:36pm UTC](https://discourse.paraview.org/t/issues-with-catalyst-2-0-installation-failing-tests-ctest/16107 "2025-03-04T22:36:38Z")

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Hi everyone, I am trying to install Catalyst 2.0 and run ctest, but I am encountering multiple test failures. I have followed the official documentation: :link: Catalyst 2.0 Build & Install Guide System Information: O…

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## [CMake Error: Unknown Command c\_install\_targets When Configuring Catalyst2](https://discourse.paraview.org/t/cmake-error-unknown-command-c-install-targets-when-configuring-catalyst2/15773)

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**Author:** [@Bhavesh](https://discourse.paraview.org/u/Bhavesh)\
**Replies:** 2\
**Last updated:** [February 26, 2025, 7:35pm UTC](https://discourse.paraview.org/t/cmake-error-unknown-command-c-install-targets-when-configuring-catalyst2/15773 "2025-02-26T19:35:20Z")

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Hi everyone, I am trying to build Catalyst2 from the source code on a Windows 10 system using the following setup: CMake Version: 3.31.0 Paraview Version: 5.12.1 Generator: Ninja Compilers: GNU 14.1.0 Source Directory:…

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## [code is hanging in the initialization](https://discourse.paraview.org/t/code-is-hanging-in-the-initialization/16244)

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**Author:** [@uturuncoglu](https://discourse.paraview.org/u/uturuncoglu)\
**Replies:** 3\
**Last updated:** [February 26, 2025, 5:12pm UTC](https://discourse.paraview.org/t/code-is-hanging-in-the-initialization/16244 "2025-02-26T17:12:10Z")

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I am trying to use catalyst in my simulation code. I have node properly set up for the initialization { "catalyst": { "scripts": { "script1": { "filename": { "dtype"…

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## [paraview catalyst docs, howtos, etc.](https://discourse.paraview.org/t/paraview-catalyst-docs-howtos-etc/16237)

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**Author:** [@ewbethel](https://discourse.paraview.org/u/ewbethel)\
**Replies:** 1\
**Last updated:** [February 25, 2025, 3:47pm UTC](https://discourse.paraview.org/t/paraview-catalyst-docs-howtos-etc/16237 "2025-02-25T15:47:08Z")

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Hi, I have a student starting work on a project that entails PV+Catalyst as an in situ endpoint. My specific question is “where are the docs for Catalyst”, including sample code. This web page – https://www.paraview.or…

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## [How to setup vtkIceTCompositePass to show composited image?](https://discourse.paraview.org/t/how-to-setup-vtkicetcompositepass-to-show-composited-image/16172)

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**Author:** [@lijian\_cug](https://discourse.paraview.org/u/lijian_cug)\
**Replies:** 0\
**Last updated:** [February 13, 2025, 8:56am UTC](https://discourse.paraview.org/t/how-to-setup-vtkicetcompositepass-to-show-composited-image/16172 "2025-02-13T08:56:34Z")

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Dear Developers: Now I use VTK and IceT in my MPI-based hydrodynamic code, and I don’t use Catalyst in-situ visualization. I have run TestSimpleIceTCompositePass code normally, but the tile-display show in every process…

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## [Load UBC mesh and model, then rotate.](https://discourse.paraview.org/t/load-ubc-mesh-and-model-then-rotate/15767)

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**Author:** [@rapidgeo](https://discourse.paraview.org/u/rapidgeo)\
**Replies:** 2\
**Last updated:** [November 25, 2024, 12:03pm UTC](https://discourse.paraview.org/t/load-ubc-mesh-and-model-then-rotate/15767 "2024-11-25T12:03:42Z")

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Hi, hope this is posted in the correct spot. I am trying to load a UBC 3D model and associated mesh file. The convention is to provide a single X,Y,Z coordinate to build the mesh and 3D model elements. This assumes no…

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## [Building ParaView with int64 MPI enabled](https://discourse.paraview.org/t/building-paraview-with-int64-mpi-enabled/15561)

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**Author:** [@Alexandre\_Minot](https://discourse.paraview.org/u/Alexandre_Minot)\
**Replies:** 4\
**Last updated:** [October 15, 2024, 9:42pm UTC](https://discourse.paraview.org/t/building-paraview-with-int64-mpi-enabled/15561 "2024-10-15T21:42:43Z")

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Hello, We got the following error saving a slice of a large case with Catalyst. The error seems to be coming from the CGNS writer, which would have been called by the CGNS Extractor. vtkMPICommunicator.cxx:205 WARN| …

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