# Development

**URL:** https://discourse.paraview.org/c/development/6.md?no_subcategories=false&page=2

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

**Page:** 3

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## [How to specify a namespace for SourceProxy in the XML file?](https://discourse.paraview.org/t/how-to-specify-a-namespace-for-sourceproxy-in-the-xml-file/17230)

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**Author:** [@CsatiZoltan](https://discourse.paraview.org/u/CsatiZoltan)\
**Replies:** 6\
**Last updated:** [October 6, 2025, 1:02pm UTC](https://discourse.paraview.org/t/how-to-specify-a-namespace-for-sourceproxy-in-the-xml-file/17230 "2025-10-06T13:02:20Z")

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Hello, My ParaView plugin works fine for a C++ class MyClass. However, when I put the class in a namespace mynamescape, ParaView does not recognize it, leading to a crash with the well-known message “This typically mean…

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## [How to implement a custom reader plugin in C++?](https://discourse.paraview.org/t/how-to-implement-a-custom-reader-plugin-in-c/17196)

<div class="topic-metadata">

**Author:** [@CsatiZoltan](https://discourse.paraview.org/u/CsatiZoltan)\
**Replies:** 3\
**Last updated:** [September 24, 2025, 8:45am UTC](https://discourse.paraview.org/t/how-to-implement-a-custom-reader-plugin-in-c/17196 "2025-09-24T08:45:35Z")

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Hi, So far, I managed to set up the build system for my ParaView plugin. The plugin compiles and I can load it in ParaView. When I try to open a file with .meshb extension, for which I develop this plugin, ParaView quit…

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## [Possible to create a ParaView plugin for a non-module based VTK library?](https://discourse.paraview.org/t/possible-to-create-a-paraview-plugin-for-a-non-module-based-vtk-library/17194)

<div class="topic-metadata">

**Author:** [@CsatiZoltan](https://discourse.paraview.org/u/CsatiZoltan)\
**Replies:** 4\
**Last updated:** [September 19, 2025, 12:50pm UTC](https://discourse.paraview.org/t/possible-to-create-a-paraview-plugin-for-a-non-module-based-vtk-library/17194 "2025-09-19T12:50:48Z")

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Hi, I want to create a new reader in a modular way: usable as a C++ library expose the main functionalities to Python create a ParaView plugin for it Before implementing the main logic – reading our mesh format into …

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## [Loading too many particles results in Server Disconnected](https://discourse.paraview.org/t/loading-too-many-particles-results-in-server-disconnected/17064)

<div class="topic-metadata">

**Author:** [@enricsosa](https://discourse.paraview.org/u/enricsosa)\
**Replies:** 10\
**Last updated:** [September 17, 2025, 7:59am UTC](https://discourse.paraview.org/t/loading-too-many-particles-results-in-server-disconnected/17064 "2025-09-17T07:59:32Z")

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Hello, To give some context to my problem, I am using a custom Python plugin that, in short, reads from a file, then transforms the data to numpy, and subsequently converts it to vtk format (vtkPoints) for visualization…

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## [Cell Grid](https://discourse.paraview.org/t/cell-grid/17178)

<div class="topic-metadata">

**Author:** [@Frankx9](https://discourse.paraview.org/u/Frankx9)\
**Replies:** 3\
**Last updated:** [September 12, 2025, 8:50am UTC](https://discourse.paraview.org/t/cell-grid/17178 "2025-09-12T08:50:48Z")

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Hi, could you point me out to where do I find a file example of the novel CellGrid that is in Paraview that I can potentially download and inspect? Any further documentation that I might look at while trying to impleme…

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## [Drag and drop in custom application does not work](https://discourse.paraview.org/t/drag-and-drop-in-custom-application-does-not-work/17172)

<div class="topic-metadata">

**Author:** [@CsatiZoltan](https://discourse.paraview.org/u/CsatiZoltan)\
**Replies:** 6\
**Last updated:** [September 9, 2025, 3:57pm UTC](https://discourse.paraview.org/t/drag-and-drop-in-custom-application-does-not-work/17172 "2025-09-09T15:57:19Z")

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Hi, I built ParaView from the master branch, then used this ParaView to build the SimpleParaView example application. Drag & drop a file to the render window works in ParaView that I built, but not in the custom applica…

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## [Raytracing Options](https://discourse.paraview.org/t/raytracing-options/17153)

<div class="topic-metadata">

**Author:** [@Stride47](https://discourse.paraview.org/u/Stride47)\
**Replies:** 3\
**Last updated:** [September 5, 2025, 7:45am UTC](https://discourse.paraview.org/t/raytracing-options/17153 "2025-09-05T07:45:00Z")

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Hello, I’m a huge fan of the raytracing option and I use it every time I can to enhance my results. However there is something annoying I notice while using it : there is no distinction between viewport and renderer as …

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## [Gradient filter broken in paraview 6.0](https://discourse.paraview.org/t/gradient-filter-broken-in-paraview-6-0/17154)

<div class="topic-metadata">

**Author:** [@T-Wainwright](https://discourse.paraview.org/u/T-Wainwright)\
**Replies:** 1\
**Last updated:** [September 4, 2025, 3:51pm UTC](https://discourse.paraview.org/t/gradient-filter-broken-in-paraview-6-0/17154 "2025-09-04T15:51:57Z")

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The gradient filter is broken in paraview 6.0- taking a simple filter over unstructured data will lead to paraview completely bailing and shutting down. Attached simple example: load → gradient → crash Maybe for discus…

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## [The color of menus](https://discourse.paraview.org/t/the-color-of-menus/17062)

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**Author:** [@jeDuck](https://discourse.paraview.org/u/jeDuck)\
**Replies:** 11\
**Last updated:** [August 27, 2025, 1:37pm UTC](https://discourse.paraview.org/t/the-color-of-menus/17062 "2025-08-27T13:37:26Z")

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Hello! All main menus, such as File, Edit, View, Objects e.t.c. have actions of white color. The actions in Filters and Extractors have gray color, the same as color as the panel with menus. Why are they different? Can I…

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## [Unexpected Behavior for StreamTracer on Multiresolution Unstructured Grid](https://discourse.paraview.org/t/unexpected-behavior-for-streamtracer-on-multiresolution-unstructured-grid/17138)

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**Author:** [@TimGerrits](https://discourse.paraview.org/u/TimGerrits)\
**Replies:** 4\
**Last updated:** [August 26, 2025, 8:00am UTC](https://discourse.paraview.org/t/unexpected-behavior-for-streamtracer-on-multiresolution-unstructured-grid/17138 "2025-08-26T08:00:18Z")

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Dear all, I have encountered a weird issue that occurs in ParaView 6.0. I am working on a multiresolution unstructured grid files where there are overlapping faces on transitions from one resolution to another. (I hav…

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## [Expanding ParaView Catalyst Source Mechanism](https://discourse.paraview.org/t/expanding-paraview-catalyst-source-mechanism/17056)

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**Author:** [@Bob\_Obara](https://discourse.paraview.org/u/Bob_Obara)\
**Replies:** 7\
**Last updated:** [August 25, 2025, 9:15am UTC](https://discourse.paraview.org/t/expanding-paraview-catalyst-source-mechanism/17056 "2025-08-25T09:15:56Z")

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In the current implementation, it is difficult to extend how channels in a Catalyst Conduit tree get mapped to sources in ParaView pipelines. What I propose here is to make this process a bit more flexible and to allow P…

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## [Unselectable options in menus are fuzzy](https://discourse.paraview.org/t/unselectable-options-in-menus-are-fuzzy/17068)

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**Author:** [@GregVernon](https://discourse.paraview.org/u/GregVernon)\
**Replies:** 5\
**Last updated:** [August 21, 2025, 11:43pm UTC](https://discourse.paraview.org/t/unselectable-options-in-menus-are-fuzzy/17068 "2025-08-21T23:43:18Z")

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I’m using the 6.0.0 release and am noticing that unselectable items in menus appear “fuzzy” – almost like there’s a shadow on the font? Once the item becomes selectable, e.g., if I rotate my view so that Camera Undo …

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## [vtkExodusIIReader: How to Output a Partitioned Dataset Instead of a Multiblock](https://discourse.paraview.org/t/vtkexodusiireader-how-to-output-a-partitioned-dataset-instead-of-a-multiblock/17043)

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**Author:** [@GeoMomo](https://discourse.paraview.org/u/GeoMomo)\
**Replies:** 2\
**Last updated:** [August 4, 2025, 3:41pm UTC](https://discourse.paraview.org/t/vtkexodusiireader-how-to-output-a-partitioned-dataset-instead-of-a-multiblock/17043 "2025-08-04T15:41:57Z")

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Dear All, This post follows up on Mathieu Westphal’s publication regarding the transition from multiblock structures to partitioned datasets: (Transition from multiblock to partitioned datasets in VTK and ParaView, a co…

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## [Adding configurable paraview resource\_dir](https://discourse.paraview.org/t/adding-configurable-paraview-resource-dir/17018)

<div class="topic-metadata">

**Author:** [@qbisi](https://discourse.paraview.org/u/qbisi)\
**Replies:** 2\
**Last updated:** [August 4, 2025, 2:40pm UTC](https://discourse.paraview.org/t/adding-configurable-paraview-resource-dir/17018 "2025-08-04T14:40:31Z")

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I am building ParaView with an external VTK. Everything looks fine, except that ParaView cannot find the documentation or examples. I investigated a bit into the function: std::string vtkPVFileInformation::GetParaViewS…

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## [Does paraview filter automatically update its properties?](https://discourse.paraview.org/t/does-paraview-filter-automatically-update-its-properties/17020)

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**Author:** [@Northern\_Condor](https://discourse.paraview.org/u/Northern_Condor)\
**Replies:** 4\
**Last updated:** [August 4, 2025, 12:55pm UTC](https://discourse.paraview.org/t/does-paraview-filter-automatically-update-its-properties/17020 "2025-08-04T12:55:02Z")

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Hello! Lets say I have a filter, with properties “a” and “b”, both ints And for some values of “a”, “b” is fixed and set by filter. For example, for a = 1, b is always 5 So, if i write from Python: And then f.a = 1…

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## [Picking in custom (C++) PV application](https://discourse.paraview.org/t/picking-in-custom-c-pv-application/16977)

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**Author:** [@nenad-vujicic](https://discourse.paraview.org/u/nenad-vujicic)\
**Replies:** 1\
**Last updated:** [July 28, 2025, 1:45pm UTC](https://discourse.paraview.org/t/picking-in-custom-c-pv-application/16977 "2025-07-28T13:45:43Z")

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Hello everyone, I’m developing custom PV based application using C++ (v6.0.0-RC2, Windows, VS2022). I created manually UI (using Qt designer), created several pqRenderView instances (using pqObjectBuilder, I didn’t use …

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## [Proposal: add a way to access ParaView's requested time in Python Calculator/Annotation](https://discourse.paraview.org/t/proposal-add-a-way-to-access-paraviews-requested-time-in-python-calculator-annotation/16903)

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**Author:** [@cory.quammen](https://discourse.paraview.org/u/cory.quammen)\
**Replies:** 6\
**Last updated:** [July 22, 2025, 2:56pm UTC](https://discourse.paraview.org/t/proposal-add-a-way-to-access-paraviews-requested-time-in-python-calculator-annotation/16903 "2025-07-22T14:56:17Z")

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The Python Calculator and Python Annotation filter let you refer to the current time and time index of the source they are connected to via the t\_value and t\_index variables and the {timevalue} and {timeindex} string sub…

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## [Paraview, Unresolved external symbol, MSVC, DLL](https://discourse.paraview.org/t/paraview-unresolved-external-symbol-msvc-dll/16928)

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**Author:** [@viktor-vad](https://discourse.paraview.org/u/viktor-vad)\
**Replies:** 1\
**Last updated:** [July 15, 2025, 7:41am UTC](https://discourse.paraview.org/t/paraview-unresolved-external-symbol-msvc-dll/16928 "2025-07-15T07:41:21Z")

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I have been attempting to build paraview app with default filters as shared. I started building it some versions and commits ago, with QT5. Now I tried with QT6. Same problem. While building target pqApplicationCompon…

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## [Annoying "feature" of the BivariateManager](https://discourse.paraview.org/t/annoying-feature-of-the-bivariatemanager/16862)

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**Author:** [@cobo](https://discourse.paraview.org/u/cobo)\
**Replies:** 8\
**Last updated:** [July 2, 2025, 9:22am UTC](https://discourse.paraview.org/t/annoying-feature-of-the-bivariatemanager/16862 "2025-07-02T09:22:48Z")

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If the BivariateManager plugin is part of a ParaView project and the user loads a state file, he will often have to choose the “Use filenames from state” option, if e.g. he wants to open a state file from somebody else t…

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## [About integration of CFSReader](https://discourse.paraview.org/t/about-integration-of-cfsreader/9111)

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**Author:** [@Fabian](https://discourse.paraview.org/u/Fabian)\
**Replies:** 28\
**Last updated:** [July 1, 2025, 1:21pm UTC](https://discourse.paraview.org/t/about-integration-of-cfsreader/9111 "2025-07-01T13:21:42Z")

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I’m a developer of the free coupled field FEM and structural optimization tool openCFS https://www.opencfs.org It originates in academia and is now free and open (MIT-License). Our data format is based on hdf5 and we us…

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## [Documentation for using mult-threading via MPI in Trame/Paraview app](https://discourse.paraview.org/t/documentation-for-using-mult-threading-via-mpi-in-trame-paraview-app/16813)

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**Author:** [@Stacey.Whitmore](https://discourse.paraview.org/u/Stacey.Whitmore)\
**Replies:** 2\
**Last updated:** [June 14, 2025, 2:56am UTC](https://discourse.paraview.org/t/documentation-for-using-mult-threading-via-mpi-in-trame-paraview-app/16813 "2025-06-14T02:56:47Z")

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Hi. I’m looking to utilize mult-threading in a Trame/Paraview app utilizing MPI and possibly PvBatch. Although I have found some documentation for using MPI and PvBatch within ParaView I was wondering if there was some P…

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## [compile ParaView superbuild with Qt6 on windows, cmake arguments](https://discourse.paraview.org/t/compile-paraview-superbuild-with-qt6-on-windows-cmake-arguments/16747)

<div class="topic-metadata">

**Author:** [@simonmssu](https://discourse.paraview.org/u/simonmssu)\
**Replies:** 4\
**Last updated:** [June 12, 2025, 2:40am UTC](https://discourse.paraview.org/t/compile-paraview-superbuild-with-qt6-on-windows-cmake-arguments/16747 "2025-06-12T02:40:39Z")

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I was able to get ParaView Superbuild with qt5 using the the following cmake flag -DENABLE\_qt5:BOOL=ON Since qt5 is out of support this month, I was trying out qt6 using -DENABLE\_qt6:BOOL=ON but end up getting a coup…

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## [Assembly nodes in Multiblock Inspector expanded too far down the hierarchy](https://discourse.paraview.org/t/assembly-nodes-in-multiblock-inspector-expanded-too-far-down-the-hierarchy/16790)

<div class="topic-metadata">

**Author:** [@Tim\_Tautges](https://discourse.paraview.org/u/Tim_Tautges)\
**Replies:** 3\
**Last updated:** [June 11, 2025, 7:45am UTC](https://discourse.paraview.org/t/assembly-nodes-in-multiblock-inspector-expanded-too-far-down-the-hierarchy/16790 "2025-06-11T07:45:07Z")

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Hi all. I’ve implemented using PDC and vtkDataAssembly in my reader and it helps immensely, easier and much more efficient. One problem though: node hierarchy is expanded up to 4 levels down in the tree, and that’s unwie…

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## [vtkPartitionedDataSetCollection + block-specific properties](https://discourse.paraview.org/t/vtkpartitioneddatasetcollection-block-specific-properties/16778)

<div class="topic-metadata">

**Author:** [@Tim\_Tautges](https://discourse.paraview.org/u/Tim_Tautges)\
**Replies:** 3\
**Last updated:** [June 10, 2025, 7:54am UTC](https://discourse.paraview.org/t/vtkpartitioneddatasetcollection-block-specific-properties/16778 "2025-06-10T07:54:36Z")

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I’m implementing a reader plugin that outputs a PDC that also displays a vtkDataAssembly with a hierarchy of nodes. I’d like some of the nodes in this assembly to have different display properties. Specifically, I’m want…

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## [How does ParaView work with Wayland and how will it work in the future ?](https://discourse.paraview.org/t/how-does-paraview-work-with-wayland-and-how-will-it-work-in-the-future/16770)

<div class="topic-metadata">

**Author:** [@mwestphal](https://discourse.paraview.org/u/mwestphal)\
**Replies:** 1\
**Last updated:** [June 3, 2025, 2:53pm UTC](https://discourse.paraview.org/t/how-does-paraview-work-with-wayland-and-how-will-it-work-in-the-future/16770 "2025-06-03T14:53:24Z")

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Introduction How does ParaView work with Wayland and how will it work in the future ? Wayland 1 is a windowing protocol and is implemented in the Weston compositor, but others exist. Wayland is designed as a replacement…

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## [write vkthdf file with points only.](https://discourse.paraview.org/t/write-vkthdf-file-with-points-only/16729)

<div class="topic-metadata">

**Author:** [@KS\_HH](https://discourse.paraview.org/u/KS_HH)\
**Replies:** 2\
**Last updated:** [June 2, 2025, 7:07pm UTC](https://discourse.paraview.org/t/write-vkthdf-file-with-points-only/16729 "2025-06-02T19:07:50Z")

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I am trying to understand how to write a vtkhdf file. To that end I tried to make it as simple as possible and write only points with point data. My script looks like this: import h5py as h5 import numpy as np pnts …

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## [libhdf5.so.103 not found when sourced openfoam (. ~/OpenFOAM-v2412/etc/bashrc)](https://discourse.paraview.org/t/libhdf5-so-103-not-found-when-sourced-openfoam-openfoam-v2412-etc-bashrc/16428)

<div class="topic-metadata">

**Author:** [@muezabdalla](https://discourse.paraview.org/u/muezabdalla)\
**Replies:** 2\
**Last updated:** [May 22, 2025, 1:51pm UTC](https://discourse.paraview.org/t/libhdf5-so-103-not-found-when-sourced-openfoam-openfoam-v2412-etc-bashrc/16428 "2025-05-22T13:51:28Z")

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after sourcing openfoam (. ~/OpenFOAM-v2412/etc/bashrc) then trying to open paraview I get this error ~/ParaView-5.13.3-MPI-Linux-Python3.10-x86\_64/bin/paraview-real:error while loading shared libraries: libhdf5.so.103:…

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## [Change values of array of selected elements](https://discourse.paraview.org/t/change-values-of-array-of-selected-elements/16644)

<div class="topic-metadata">

**Author:** [@Clockwork](https://discourse.paraview.org/u/Clockwork)\
**Replies:** 1\
**Last updated:** [May 19, 2025, 6:34pm UTC](https://discourse.paraview.org/t/change-values-of-array-of-selected-elements/16644 "2025-05-19T18:34:17Z")

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I have a method of selecting cells and changing the values in that portion of the array to a new integer, but it is quite cumbersome. So, for example, I might have a mesh that has a “Region” cell array with all integer …

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## [Paraview conflicting with local Python installation](https://discourse.paraview.org/t/paraview-conflicting-with-local-python-installation/16582)

<div class="topic-metadata">

**Author:** [@ar505](https://discourse.paraview.org/u/ar505)\
**Replies:** 1\
**Last updated:** [May 14, 2025, 1:29pm UTC](https://discourse.paraview.org/t/paraview-conflicting-with-local-python-installation/16582 "2025-05-14T13:29:58Z")

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I have a case where I cannot run paraview server manager commands from Python Shell in Paraview where there is local Python installation. When I load a case and enter the command GetActiveSource() , it will fail. If I re…

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## [streamline termination when using surface streamlines with group of surfaces since 5.10](https://discourse.paraview.org/t/streamline-termination-when-using-surface-streamlines-with-group-of-surfaces-since-5-10/16607)

<div class="topic-metadata">

**Author:** [@Jnsn](https://discourse.paraview.org/u/Jnsn)\
**Replies:** 2\
**Last updated:** [May 13, 2025, 12:23pm UTC](https://discourse.paraview.org/t/streamline-termination-when-using-surface-streamlines-with-group-of-surfaces-since-5-10/16607 "2025-05-13T12:23:50Z")

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I am using the streamTracerWithCustomSource filter to generate streamlines on a surface. The data is from a CFD simulation, flow around a ship (similar to the OpenFOAM DTCHull tutorial, but for simplicity here only singl…

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