# \#python3

**URL:** https://discourse.mcneel.com/tag/python3/2323.md

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## [Plugin: Python3 shared libraries and Grasshopper components](https://discourse.mcneel.com/t/plugin-python3-shared-libraries-and-grasshopper-components/217276)

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**Author:** [@Iljya\_Kalai](https://discourse.mcneel.com/u/Iljya_Kalai)\
**Replies:** 2\
**Last updated:** [March 24, 2026, 10:22pm UTC](https://discourse.mcneel.com/t/plugin-python3-shared-libraries-and-grasshopper-components/217276 "2026-03-24T22:22:04Z")

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Hi, Is there an example open-source Grasshopper plugin that uses a shared Python3 library that I could look at? I’ve read the “Creating Rhino/Grasshopper Script Plugins” guide (and several others), but cannot seem to l…

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## [The "Wallacei X (Wallacei X)" object expired during a solution](https://discourse.mcneel.com/t/the-wallacei-x-wallacei-x-object-expired-during-a-solution/211261)

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**Author:** [@Hanbing\_Zhao](https://discourse.mcneel.com/u/Hanbing_Zhao)\
**Replies:** 6\
**Last updated:** [October 28, 2025, 10:01am UTC](https://discourse.mcneel.com/t/the-wallacei-x-wallacei-x-object-expired-during-a-solution/211261 "2025-10-28T10:01:26Z")

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I’m working with Wallacei in Rhino 8 and using a customized Python script to generate input objectives. I’m also incorporating Karamba analysis results as part of the objective input. However, I’m encountering multiple e…

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## [GetString only displays 3 string options?](https://discourse.mcneel.com/t/getstring-only-displays-3-string-options/206058)

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**Author:** [@Tommy804](https://discourse.mcneel.com/u/Tommy804)\
**Replies:** 2\
**Last updated:** [June 17, 2025, 11:35pm UTC](https://discourse.mcneel.com/t/getstring-only-displays-3-string-options/206058 "2025-06-17T23:35:40Z")

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Does GetString have a limit to the amount of strings shown in the command line? I’m trying to test using it with 5 options but it doesn’t display them all and also only ever shows “Connector”, “Sunfly” , or “Custom”. Im …

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## [Issue with Python 3, python39.dll conflict](https://discourse.mcneel.com/t/issue-with-python-3-python39-dll-conflict/189591)

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**Author:** [@Aleksander.Mastalski](https://discourse.mcneel.com/u/Aleksander.Mastalski)\
**Replies:** 1\
**Last updated:** [May 12, 2025, 3:50pm UTC](https://discourse.mcneel.com/t/issue-with-python-3-python39-dll-conflict/189591 "2025-05-12T15:50:04Z")

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Hello, I have been recently testing the python 3 script editor in grasshopper and rhino 8. My main focus was on installing the external packages (networkx in this example) I encountered the issue with python versions …

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## [Help Updating Eto.Drawable Graphics - Cross-Class Communication](https://discourse.mcneel.com/t/help-updating-eto-drawable-graphics-cross-class-communication/180505)

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**Author:** [@michaelvollrath](https://discourse.mcneel.com/u/michaelvollrath)\
**Replies:** 29\
**Last updated:** [April 14, 2025, 5:43pm UTC](https://discourse.mcneel.com/t/help-updating-eto-drawable-graphics-cross-class-communication/180505 "2025-04-14T17:43:25Z")

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Hello, I’m using drawables for different parts of a UI “toolbar” called “MainToolbar” in my code. I have a drawable “button” called “TrayToggle” that updates a global boolean called “show\_tray” when clicked. When I cl…

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## [GH Python3 'site-envs' life-cycle behavior?](https://discourse.mcneel.com/t/gh-python3-site-envs-life-cycle-behavior/182642)

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**Author:** [@ed.p.may](https://discourse.mcneel.com/u/ed.p.may)\
**Replies:** 1\
**Last updated:** [April 8, 2025, 9:06pm UTC](https://discourse.mcneel.com/t/gh-python3-site-envs-life-cycle-behavior/182642 "2025-04-08T21:06:12Z")

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Hi, I am starting to dip a toe into the new RH-8 Python3 components in Grasshopper. I wonder if there is some documentation regarding how the interpreter will behave that I might refer to as I try and understand this ne…

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## [Python39 Plugin for Rhino8](https://discourse.mcneel.com/t/python39-plugin-for-rhino8/199436)

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**Author:** [@Niko\_Striega](https://discourse.mcneel.com/u/Niko_Striega)\
**Replies:** 6\
**Last updated:** [February 14, 2025, 1:25am UTC](https://discourse.mcneel.com/t/python39-plugin-for-rhino8/199436 "2025-02-14T01:25:07Z")

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Where do I find the Python3 Plugin for Rhino8? I only have a Plugin for IronPython and I would like to use Python39

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## [Python3: Can not remove module path](https://discourse.mcneel.com/t/python3-can-not-remove-module-path/182683)

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**Author:** [@ed.p.may](https://discourse.mcneel.com/u/ed.p.may)\
**Replies:** 3\
**Last updated:** [January 27, 2025, 6:18am UTC](https://discourse.mcneel.com/t/python3-can-not-remove-module-path/182683 "2025-01-27T06:18:31Z")

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I was testing some things, and added a path via the new Python3 / Tools / Options / Python3 / Module Search Path GUI and now it can’t be removed? I have ‘deleted’ it several times now using the trash-can icon, and ha…

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## [How to open Python3 component with a clean canvas in GH?](https://discourse.mcneel.com/t/how-to-open-python3-component-with-a-clean-canvas-in-gh/198063)

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**Author:** [@vin.iab](https://discourse.mcneel.com/u/vin.iab)\
**Replies:** 3\
**Last updated:** [January 21, 2025, 8:10am UTC](https://discourse.mcneel.com/t/how-to-open-python3-component-with-a-clean-canvas-in-gh/198063 "2025-01-21T08:10:25Z")

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Hi, I am starting to use Python3 in Grasshopper. I would like to know if there is a way to open the Python3 component’s script editor in grasshopper without any syntax as introduction or something else, just to eliminat…

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## [How to get input values from input params generated in python script](https://discourse.mcneel.com/t/how-to-get-input-values-from-input-params-generated-in-python-script/197585)

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**Author:** [@OBucklin](https://discourse.mcneel.com/u/OBucklin)\
**Replies:** 3\
**Last updated:** [January 13, 2025, 10:01am UTC](https://discourse.mcneel.com/t/how-to-get-input-values-from-input-params-generated-in-python-script/197585 "2025-01-13T10:01:11Z")

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Hello, I am trying to port IronPython scripts to Rhino8/python3. We have a bunch of Components that append input params dynamically. I can now add the input params, but they do not collect any data. I can see by printin…

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## [Access is denied \_umath\_linalg.cp39-win\_amd64.pyd](https://discourse.mcneel.com/t/access-is-denied-umath-linalg-cp39-win-amd64-pyd/192211)

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**Author:** [@Mat\_S](https://discourse.mcneel.com/u/Mat_S)\
**Replies:** 2\
**Last updated:** [November 21, 2024, 2:20am UTC](https://discourse.mcneel.com/t/access-is-denied-umath-linalg-cp39-win-amd64-pyd/192211 "2024-11-21T02:20:54Z")

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I am using # r: for some modules that use numpy. It seems there is some conflict. On first run this error appears: ERROR: Exception: Traceback (most recent call last): File "C:\\Users\\local user\\.rhinocode\\py39-rh8\\…

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## [Python 3 Script for GH: error in converting numpy eigenvectors (Rhino8)](https://discourse.mcneel.com/t/python-3-script-for-gh-error-in-converting-numpy-eigenvectors-rhino8/194414)

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**Author:** [@Arianna\_Venettoni](https://discourse.mcneel.com/u/Arianna_Venettoni)\
**Replies:** 4\
**Last updated:** [November 11, 2024, 3:24pm UTC](https://discourse.mcneel.com/t/python-3-script-for-gh-error-in-converting-numpy-eigenvectors-rhino8/194414 "2024-11-11T15:24:48Z")

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Hi everyone. I’m nwew to Python so I’m sorry if the question may be silly, but I’m really doing my best. I’m trying to create a simple script that uses numpy in Python 3 script in GH. I want to extract the eigenvector…

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## [Cannot add script components to canvas](https://discourse.mcneel.com/t/cannot-add-script-components-to-canvas/192975)

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**Author:** [@OBucklin](https://discourse.mcneel.com/u/OBucklin)\
**Replies:** 18\
**Last updated:** [November 5, 2024, 3:58pm UTC](https://discourse.mcneel.com/t/cannot-add-script-components-to-canvas/192975 "2024-11-05T15:58:08Z")

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Hello, I am unable to add any script components to the canvas. Originally I got the following error window: I updated the permissions to allow writing in that Rhino 8 folder. Now when adding a python3 or IronPytho…

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## [Transferring data between Python components](https://discourse.mcneel.com/t/transferring-data-between-python-components/193011)

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**Author:** [@YCoCg](https://discourse.mcneel.com/u/YCoCg)\
**Replies:** 10\
**Last updated:** [October 29, 2024, 11:31pm UTC](https://discourse.mcneel.com/t/transferring-data-between-python-components/193011 "2024-10-29T23:31:54Z")

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I am having trouble understanding how I am supposed to handle inputs/outputs for the Python 3 component in Rhino 8. It’s different to Rhino 7 where Python lists automatically become Grasshopper lists. Searching around I…

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## [Problem reading GraphML file data with Python code](https://discourse.mcneel.com/t/problem-reading-graphml-file-data-with-python-code/192809)

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**Author:** [@kalantarisaeede](https://discourse.mcneel.com/u/kalantarisaeede)\
**Replies:** 2\
**Last updated:** [October 12, 2024, 7:38pm UTC](https://discourse.mcneel.com/t/problem-reading-graphml-file-data-with-python-code/192809 "2024-10-12T19:38:47Z")

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I have a simple python code to read the GraphML file and extract the data from the file like nodes, edges and other information. The Python code has no errors, also the GraphML file and its path are correct. But I don’t …

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## [GH Python-3 Editor: Error with ghpythonlib curve operations?](https://discourse.mcneel.com/t/gh-python-3-editor-error-with-ghpythonlib-curve-operations/175064)

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**Author:** [@ed.p.may](https://discourse.mcneel.com/u/ed.p.may)\
**Replies:** 6\
**Last updated:** [September 27, 2024, 12:53pm UTC](https://discourse.mcneel.com/t/gh-python-3-editor-error-with-ghpythonlib-curve-operations/175064 "2024-09-27T12:53:41Z")

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Using ghpythonlib.components within the new Python3 editor in Grasshopper. Running the code: import ghpythonlib.components as ghc a = ghc.ControlPoints(x).points on a single Polyline. In old GHPython component it works…

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## [Calling structure constructors using named arguments: Python 2 vs. 3](https://discourse.mcneel.com/t/calling-structure-constructors-using-named-arguments-python-2-vs-3/188842)

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**Author:** [@spb](https://discourse.mcneel.com/u/spb)\
**Replies:** 1\
**Last updated:** [August 6, 2024, 7:28pm UTC](https://discourse.mcneel.com/t/calling-structure-constructors-using-named-arguments-python-2-vs-3/188842 "2024-08-06T19:28:30Z")

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8.9.24194.18121, 2024-07-12 import Rhino torusA = Rhino.Geometry.Torus( basePlane=Rhino.Geometry.Plane.WorldXY, majorRadius=20.0, minorRadius=10.0) sEval = "torusA.IsValid"; print("{}: {}".format(sEval, ev…

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## [ETO GridView rhino 8 and python 3](https://discourse.mcneel.com/t/eto-gridview-rhino-8-and-python-3/183621)

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**Author:** [@etiennekasteel](https://discourse.mcneel.com/u/etiennekasteel)\
**Replies:** 2\
**Last updated:** [June 14, 2024, 12:16pm UTC](https://discourse.mcneel.com/t/eto-gridview-rhino-8-and-python-3/183621 "2024-06-14T12:16:15Z")

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Hi all, Trying to create a simple ETO modeless dialog in Rhino 8 and Python 3 with a GridView. I cannot seem to get the DataStore contents to render in the table. The data does exist, and adding a ClickEvent shows that…

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## [GH Python3 Dependency Versions Behavior?](https://discourse.mcneel.com/t/gh-python3-dependency-versions-behavior/182644)

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**Author:** [@ed.p.may](https://discourse.mcneel.com/u/ed.p.may)\
**Replies:** 4\
**Last updated:** [May 23, 2024, 6:37pm UTC](https://discourse.mcneel.com/t/gh-python3-dependency-versions-behavior/182644 "2024-05-23T18:37:41Z")

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Hi, I wonder what the expected behavior is when multiple Grasshopper Python3 components try and pip-install dependencies with different versions? How should we anticipate that the system will behave in that case? For i…

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## [Update Sliders in Python 3](https://discourse.mcneel.com/t/update-sliders-in-python-3/180684)

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**Author:** [@claire.DP](https://discourse.mcneel.com/u/claire.DP)\
**Replies:** 0\
**Last updated:** [April 23, 2024, 8:27am UTC](https://discourse.mcneel.com/t/update-sliders-in-python-3/180684 "2024-04-23T08:27:02Z")

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Hello everyone, During my PhD research, I developed ghPython components for genetic optimization on Rhino 7 using valuable resources found on this forum. I am now planning to adapt these components to Rhino 8 using Pyth…

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## [How to access Cluster objects' content with Python3](https://discourse.mcneel.com/t/how-to-access-cluster-objects-content-with-python3/178619)

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**Author:** [@Toni\_Osterlund](https://discourse.mcneel.com/u/Toni_Osterlund)\
**Replies:** 5\
**Last updated:** [March 27, 2024, 2:44pm UTC](https://discourse.mcneel.com/t/how-to-access-cluster-objects-content-with-python3/178619 "2024-03-27T14:44:49Z")

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Hi (@dale) I’m having difficulties understanding the IGH\_DocumentObject on Python3. Accessing the contents of a GH\_Cluster in Python2 or IronPython works, but converting to Python 3, the cluster object is not a cluster…

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## [Open Teaching Material for Introduction to Programming with Python Rhino](https://discourse.mcneel.com/t/open-teaching-material-for-introduction-to-programming-with-python-rhino/175855)

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**Author:** [@andrea.settimi](https://discourse.mcneel.com/u/andrea.settimi)\
**Replies:** 0\
**Last updated:** [February 16, 2024, 2:15pm UTC](https://discourse.mcneel.com/t/open-teaching-material-for-introduction-to-programming-with-python-rhino/175855 "2024-02-16T14:15:46Z")

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Hello Rhino community! :snake::snake:We wanted to share with you all the open-source and free teaching material from our course "AR-327"\*\* which is an \*\*hands-on programming course for designers (the coursebook) taugh…

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## [No language found in Py3 component](https://discourse.mcneel.com/t/no-language-found-in-py3-component/174653)

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**Author:** [@Modeller](https://discourse.mcneel.com/u/Modeller)\
**Replies:** 0\
**Last updated:** [February 1, 2024, 8:27am UTC](https://discourse.mcneel.com/t/no-language-found-in-py3-component/174653 "2024-02-01T08:27:46Z")

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Hi! My problem is related to the use of Python 3 in Grasshopper. I have Python 3.12.1 installed on my system (installation confirmed through cmd.exe → “python --version”) and I am using Rhino 8 SR3 (8.3.24009.15001, 20…

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## [Same code but different results in GH Python3 and Python 2 components](https://discourse.mcneel.com/t/same-code-but-different-results-in-gh-python3-and-python-2-components/172896)

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**Author:** [@tpuaup](https://discourse.mcneel.com/u/tpuaup)\
**Replies:** 3\
**Last updated:** [January 17, 2024, 6:31pm UTC](https://discourse.mcneel.com/t/same-code-but-different-results-in-gh-python3-and-python-2-components/172896 "2024-01-17T18:31:08Z")

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Not sure if it’s a bug, but when I try to filter input values, it gets different result in python3 component. The code is pretty simple: if x%2 == 0: a = x else: b = x

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## [Rhino.Compute fails with python3 script component](https://discourse.mcneel.com/t/rhino-compute-fails-with-python3-script-component/172494)

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**Author:** [@Romain\_Battini](https://discourse.mcneel.com/u/Romain_Battini)\
**Replies:** 0\
**Last updated:** [January 2, 2024, 10:58am UTC](https://discourse.mcneel.com/t/rhino-compute-fails-with-python3-script-component/172494 "2024-01-02T10:58:42Z")

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Hello, I am trying to use python3 scripts in gh definition running with rhino.compute. When running a gh with no script component, everything goes fine. But when adding a python3 script component, I have the following …

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## [Grasshopper script: TextTo3D](https://discourse.mcneel.com/t/grasshopper-script-textto3d/171368)

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**Author:** [@anon39580149](https://discourse.mcneel.com/u/anon39580149)\
**Replies:** 2\
**Last updated:** [December 22, 2023, 8:28pm UTC](https://discourse.mcneel.com/t/grasshopper-script-textto3d/171368 "2023-12-22T20:28:24Z")

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Grasshopper Script Rhino8 only: Examples: https://app.meshy.ai/discover