# Latest **URL:** https://opentps.discourse.group/latest.md [Latest](https://opentps.discourse.group/latest.md) · [Categories](https://opentps.discourse.group/categories.md) · [Tags](https://opentps.discourse.group/tags.md) --- ## [Welcome to OpenTPS users community! 👋](https://opentps.discourse.group/t/welcome-to-opentps-users-community/5)
**Author:** [@system](https://opentps.discourse.group/u/system)\ **Replies:** 0\ **Last updated:** [February 27, 2024, 12:33pm UTC](https://opentps.discourse.group/t/welcome-to-opentps-users-community/5 "2024-02-27T12:33:32Z")
OpenTPS users A place to give feedback about OpenTPS, report bugs and suggest new features contact : info.opentps@gmail.com :technologist: :woman\_technologist: Find the code in gitlab: Open-MCsquare / OpenTPS · GitLa… --- ## [Proton Pencil Beam Scanning Plan utilizing apertures/multi leaf collimators](https://opentps.discourse.group/t/proton-pencil-beam-scanning-plan-utilizing-apertures-multi-leaf-collimators/112)
**Author:** [@jljw](https://opentps.discourse.group/u/jljw)\ **Replies:** 4\ **Last updated:** [September 3, 2026, 1:17am UTC](https://opentps.discourse.group/t/proton-pencil-beam-scanning-plan-utilizing-apertures-multi-leaf-collimators/112 "2026-09-03T01:17:56Z")
Hi, I’m new to openTPS and am currently looking into the generation and optimization of proton pencil beam scanning plans that incorporate apertures or multileaf collimators. I’m wondering if anyone has conducted simila… --- ## [Jupyter kernel crashes during MCsquare beamlet calculation on Linux](https://opentps.discourse.group/t/jupyter-kernel-crashes-during-mcsquare-beamlet-calculation-on-linux/131)
**Author:** [@Pongphanot](https://opentps.discourse.group/u/Pongphanot)\ **Replies:** 1\ **Last updated:** [August 31, 2026, 12:53pm UTC](https://opentps.discourse.group/t/jupyter-kernel-crashes-during-mcsquare-beamlet-calculation-on-linux/131 "2026-08-31T12:53:55Z")
Hi everyone, I am having an issue running OpenTPS proton plan optimization from a Python/Jupyter workflow on Linux. Setup: Linux workstation Python 3.12 OpenTPS 3.0.1 VS Code + Jupyter The crash occurs wh… --- ## [Plugins:Flash TPS](https://opentps.discourse.group/t/plugins-flash-tps/128)
**Author:** [@ddxxwang](https://opentps.discourse.group/u/ddxxwang)\ **Replies:** 1\ **Last updated:** [August 31, 2026, 12:25pm UTC](https://opentps.discourse.group/t/plugins-flash-tps/128 "2026-08-31T12:25:46Z")
Hi OpenTPS Team, I am currently trying to install and set up the opentps\_flash extension on Ubuntu with OpenTPS release 3.0+. However, I encountered a few compatibility and installation issues during the process, mainly… --- ## [Beam delivery timing](https://opentps.discourse.group/t/beam-delivery-timing/127)
**Author:** [@jacinta](https://opentps.discourse.group/u/jacinta)\ **Replies:** 2\ **Last updated:** [June 26, 2026, 3:23pm UTC](https://opentps.discourse.group/t/beam-delivery-timing/127 "2026-06-26T15:23:41Z")
Hi, I’m trying to calculate the total delivery time for a plan i.e. irradiation time + scanning time + energy layer switching time. Starting with the example provided in “run\_PBSDeliveryTimings.py”, the outputs using p… --- ## [Dose mimicking on OpenTPS](https://opentps.discourse.group/t/dose-mimicking-on-opentps/125)
**Author:** [@leehoy](https://opentps.discourse.group/u/leehoy)\ **Replies:** 2\ **Last updated:** [April 29, 2026, 3:12am UTC](https://opentps.discourse.group/t/dose-mimicking-on-opentps/125 "2026-04-29T03:12:14Z")
Hello, I have 3D dose distribution of photon plans and would like to obtain fluence maps to deliver the dose using OpenTPS. I believe this can be done by optimizing the plans with dose-mimicking. Does OpenTPS support … --- ## [Issues with readDicomPlan for proton plans using repainting](https://opentps.discourse.group/t/issues-with-readdicomplan-for-proton-plans-using-repainting/119)
**Author:** [@mchen](https://opentps.discourse.group/u/mchen)\ **Replies:** 4\ **Last updated:** [April 7, 2026, 8:20pm UTC](https://opentps.discourse.group/t/issues-with-readdicomplan-for-proton-plans-using-repainting/119 "2026-04-07T20:20:35Z")
There is a single spot check in \_planProtonLayer. For the RTplan exported from RayStation, it will run into error when the plan have two spots at the same position. There is no time sequence in the RTplan, so the startim… --- ## [Clarification needed on BDL modeling parameters](https://opentps.discourse.group/t/clarification-needed-on-bdl-modeling-parameters/123)
**Author:** [@Cellur-574](https://opentps.discourse.group/u/Cellur-574)\ **Replies:** 5\ **Last updated:** [March 30, 2026, 2:35pm UTC](https://opentps.discourse.group/t/clarification-needed-on-bdl-modeling-parameters/123 "2026-03-30T14:35:48Z")
Dear OpenTPS Team, I am currently working on proton PBS machine modeling using OpenTPS and the underlying MCsquare engine. I have extracted my machine parameters from commissioning data but have a few specific questions… --- ## [Open-TPS for Mac ](https://opentps.discourse.group/t/open-tps-for-mac/117)
**Author:** [@Alejandro](https://opentps.discourse.group/u/Alejandro)\ **Replies:** 2\ **Last updated:** [March 10, 2026, 5:48pm UTC](https://opentps.discourse.group/t/open-tps-for-mac/117 "2026-03-10T17:48:12Z")
Hello, I am currently running OpenTPS on a Mac with Apple Silicon (M1, arm64). The OpenTPS installation itself works correctly, and the GUI launches without issues. However, I am encountering a problem when running MCsq… --- ## [Question about beam energy layer decision](https://opentps.discourse.group/t/question-about-beam-energy-layer-decision/114)
**Author:** [@chenye](https://opentps.discourse.group/u/chenye)\ **Replies:** 4\ **Last updated:** [March 4, 2026, 2:32am UTC](https://opentps.discourse.group/t/question-about-beam-energy-layer-decision/114 "2026-03-04T02:32:58Z")
Dear OpenTPS developers, The OpenTPS is a very powerful tool. Thanks a lot for your efforts. I would like to ask how to decide the nominal energy of a proton beam layer. \> opentps\_core/opentps/core/processing/doseCalc… --- ## [1st OpenTPS User Meeting – February 6th (Online)](https://opentps.discourse.group/t/1st-opentps-user-meeting-february-6th-online/113)
**Author:** [@OpenTPS](https://opentps.discourse.group/u/OpenTPS)\ **Replies:** 1\ **Last updated:** [January 28, 2026, 3:44pm UTC](https://opentps.discourse.group/t/1st-opentps-user-meeting-february-6th-online/113 "2026-01-28T15:44:29Z")
We are excited to announce the 1st OpenTPS User Meeting, an online event bringing together the OpenTPS development team and user community to share updates, experiences, challenges, and future perspectives. :date: Frida… --- ## [Bin shift in dosimetric index computation](https://opentps.discourse.group/t/bin-shift-in-dosimetric-index-computation/110)
**Author:** [@sebquet](https://opentps.discourse.group/u/sebquet)\ **Replies:** 1\ **Last updated:** [November 18, 2025, 11:02am UTC](https://opentps.discourse.group/t/bin-shift-in-dosimetric-index-computation/110 "2025-11-18T11:02:20Z")
Hi there, I had dosimetric indices that were 0 so I dug up on the code and I think there is a problem. On the below dictionnary you will see that the dosimetric indices of the heart have a problem. We cannot have a D1cc… --- ## [Outputs after generating a plan](https://opentps.discourse.group/t/outputs-after-generating-a-plan/103)
**Author:** [@NICOLAS\_IGNACIO\_BREV](https://opentps.discourse.group/u/NICOLAS_IGNACIO_BREV)\ **Replies:** 5\ **Last updated:** [November 13, 2025, 10:04am UTC](https://opentps.discourse.group/t/outputs-after-generating-a-plan/103 "2025-11-13T10:04:39Z")
Hello, after generating a plan, there’s a PlanPencil.txt file in the \\openTPS\_workspace\\Simulations\\MCsquare\_simulation path. What exactly is that file? I need to get the dose deposition matrix after generating a plan, … --- ## [Error with 'openTPS\_workspace\\\\Simulations\\\\MCsquare\_simulation\\\\Outputs\\\\Sparse\_Dose.txt'](https://opentps.discourse.group/t/error-with-opentps-workspace-simulations-mcsquare-simulation-outputs-sparse-dose-txt/101)
**Author:** [@NICOLAS\_IGNACIO\_BREV](https://opentps.discourse.group/u/NICOLAS_IGNACIO_BREV)\ **Replies:** 3\ **Last updated:** [October 30, 2025, 10:02am UTC](https://opentps.discourse.group/t/error-with-opentps-workspace-simulations-mcsquare-simulation-outputs-sparse-dose-txt/101 "2025-10-30T10:02:06Z")
I have managed to generate a plan and in the part where the ‘compute beamlets’ is done and I have this error that says that the file Sparse\_Dose.txt is not found, but the file Sparse\_Dose.bin exists in the folder, I have… --- ## [Conformity Index Calculation: to Or or not to Or Body Mask and PTV(ROI)](https://opentps.discourse.group/t/conformity-index-calculation-to-or-or-not-to-or-body-mask-and-ptv-roi/109)
**Author:** [@hosseinjafar](https://opentps.discourse.group/u/hosseinjafar)\ **Replies:** 1\ **Last updated:** [October 29, 2025, 2:16pm UTC](https://opentps.discourse.group/t/conformity-index-calculation-to-or-or-not-to-or-body-mask-and-ptv-roi/109 "2025-10-29T14:16:07Z")
Hi there, When calculating conformity index (CI), I realized some of my data have CI\>1. This happened because the body mask and the PTV mask were none overlapping when the data was exported from the clinical TPS (pictu… --- ## [Error when computing dose \[Not Found Error\]](https://opentps.discourse.group/t/error-when-computing-dose-not-found-error/108)
**Author:** [@Ronald](https://opentps.discourse.group/u/Ronald)\ **Replies:** 5\ **Last updated:** [October 27, 2025, 1:31pm UTC](https://opentps.discourse.group/t/error-when-computing-dose-not-found-error/108 "2025-10-27T13:31:37Z")
Dear Developers, Thanks for providing the powerful OpenTPS tool. I have problems when computing the MC2 dose. I have attached the screenshot of the terminal for your reference. Seems that the three ‘not found’ cause the… --- ## [Installation and startup with error for vtkSimpleImageFilterExample](https://opentps.discourse.group/t/installation-and-startup-with-error-for-vtksimpleimagefilterexample/104)
**Author:** [@Kira](https://opentps.discourse.group/u/Kira)\ **Replies:** 5\ **Last updated:** [October 14, 2025, 5:30pm UTC](https://opentps.discourse.group/t/installation-and-startup-with-error-for-vtksimpleimagefilterexample/104 "2025-10-14T17:30:16Z")
Hello, I’m completely new to OpenTPS. I just installed Anaconda on my Mac (M2) through the anaconda website. I completed the quick start steps: conda create --name OpenTPS python=3.9 conda activate OpenTPS pip install … --- ## [Bug fix in ROIContour.getBinaryMask(): up sampling contours](https://opentps.discourse.group/t/bug-fix-in-roicontour-getbinarymask-up-sampling-contours/105)
**Author:** [@hosseinjafar](https://opentps.discourse.group/u/hosseinjafar)\ **Replies:** 1\ **Last updated:** [October 14, 2025, 9:40am UTC](https://opentps.discourse.group/t/bug-fix-in-roicontour-getbinarymask-up-sampling-contours/105 "2025-10-14T09:40:59Z")
When getting contour mask from mesh, if the image z spacing (dZ\_s) is smaller than the minimum mesh vertices along the Z axis (dZ\_m), the mask is generated at every dZ\_m/dZ\_s slices. For example, on some CBCT images, whe… --- ## [Didn't order prostate fries! bug in ROIContour.getBinaryMask() where minSpatialResolution is assumed to be 1](https://opentps.discourse.group/t/didnt-order-prostate-fries-bug-in-roicontour-getbinarymask-where-minspatialresolution-is-assumed-to-be-1/102)
**Author:** [@hosseinjafar](https://opentps.discourse.group/u/hosseinjafar)\ **Replies:** 2\ **Last updated:** [September 22, 2025, 2:40pm UTC](https://opentps.discourse.group/t/didnt-order-prostate-fries-bug-in-roicontour-getbinarymask-where-minspatialresolution-is-assumed-to-be-1/102 "2025-09-22T14:40:06Z")
There is a bug in ROIContour.getBinaryMask() where minSpatialResolution is assumed to be 1. This assumption does not hold for trans rectal ultrasound scans, resulting in the “fries artifact” on when converting mask to me… --- ## [Applying computed transformation](https://opentps.discourse.group/t/applying-computed-transformation/98)
**Author:** [@MrMechine](https://opentps.discourse.group/u/MrMechine)\ **Replies:** 4\ **Last updated:** [August 28, 2025, 9:17am UTC](https://opentps.discourse.group/t/applying-computed-transformation/98 "2025-08-28T09:17:56Z")
I am using the rigid registration module to compute a registratration between two Ct scans. The compute function returns a transformation3d object. How do I apply this transformation? Do I translate the origin by the tra… --- ## [How to get beamlet?](https://opentps.discourse.group/t/how-to-get-beamlet/100)
**Author:** [@Babasucker](https://opentps.discourse.group/u/Babasucker)\ **Replies:** 1\ **Last updated:** [August 26, 2025, 1:37pm UTC](https://opentps.discourse.group/t/how-to-get-beamlet/100 "2025-08-26T13:37:58Z")
beamlets = mc2.computeBeamlets(ct, plan, roi=\[roi\]) the function cant work . or how to make it work ? --- ## [An error occurred when I tried to run the example “Simple dose computation and optimization on a real CT image”](https://opentps.discourse.group/t/an-error-occurred-when-i-tried-to-run-the-example-simple-dose-computation-and-optimization-on-a-real-ct-image/99)
**Author:** [@Babasucker](https://opentps.discourse.group/u/Babasucker)\ **Replies:** 2\ **Last updated:** [August 26, 2025, 1:32pm UTC](https://opentps.discourse.group/t/an-error-occurred-when-i-tried-to-run-the-example-simple-dose-computation-and-optimization-on-a-real-ct-image/99 "2025-08-26T13:32:24Z")
Installing I followed Quick Start (without conda on windows) set OpenTPS\_venv as .venv GUI-Dose computation after designing a plan , selection bar of Plan in the Dose computation page is still blank and when I’m ed… --- ## [Going from CT to image3d](https://opentps.discourse.group/t/going-from-ct-to-image3d/91)
**Author:** [@MrMechine](https://opentps.discourse.group/u/MrMechine)\ **Replies:** 2\ **Last updated:** [August 21, 2025, 1:50am UTC](https://opentps.discourse.group/t/going-from-ct-to-image3d/91 "2025-08-21T01:50:48Z")
I want to go from a ct scan in dicom format to a image3d object. I have been able to get the scan into a ctimage object but the registration object in the ‘opentps.core.processing.registration.registration’ module requir… --- ## [CuPy requirement for image proccessing?](https://opentps.discourse.group/t/cupy-requirement-for-image-proccessing/86)
**Author:** [@MrMechine](https://opentps.discourse.group/u/MrMechine)\ **Replies:** 3\ **Last updated:** [August 4, 2025, 9:11am UTC](https://opentps.discourse.group/t/cupy-requirement-for-image-proccessing/86 "2025-08-04T09:11:45Z")
I am looking through the image proccessing examples and I get a bunch of errors relating to me not having cupy installed. Even in the examples that arren’t CuPy examples it doesn’t work and I get this output. Is this rel… --- ## [Missing modules when running Examples](https://opentps.discourse.group/t/missing-modules-when-running-examples/76)
**Author:** [@MrMechine](https://opentps.discourse.group/u/MrMechine)\ **Replies:** 6\ **Last updated:** [July 31, 2025, 12:38am UTC](https://opentps.discourse.group/t/missing-modules-when-running-examples/76 "2025-07-31T00:38:45Z")
I am using conda and VS code. I followed the install directions for conda made sure VS Code was using the right interpreter and I still get this missing module error. How do I get this example working? Below is the termi… --- ## [KeyError: 'dir'](https://opentps.discourse.group/t/keyerror-dir/83)
**Author:** [@Stevie](https://opentps.discourse.group/u/Stevie)\ **Replies:** 5\ **Last updated:** [July 16, 2025, 5:41pm UTC](https://opentps.discourse.group/t/keyerror-dir/83 "2025-07-16T17:41:20Z")
Hello! I’m trying to build a python program that uses OpenTPS but I’m running into this issue: File “main.py”, line 8, in File “”, line 1176, in \_find\_and\_load File “”, line 1147, in \_find\_and\_load\_unlocked File “”,… --- ## [Assistance Required for Running OpenTPS Sample Case on macOS](https://opentps.discourse.group/t/assistance-required-for-running-opentps-sample-case-on-macos/64)
**Author:** [@k.khatami](https://opentps.discourse.group/u/k.khatami)\ **Replies:** 4\ **Last updated:** [July 15, 2025, 4:11pm UTC](https://opentps.discourse.group/t/assistance-required-for-running-opentps-sample-case-on-macos/64 "2025-07-15T16:11:46Z")
I am currently working on learning and testing OpenTPS on my system. I’m using a MacBook Air (Model MacBook Air MRXR3 2024 LLA), and I have successfully installed and launched OpenTPS using the Conda environment (conda a… --- ## [ModuleNotFoundError](https://opentps.discourse.group/t/modulenotfounderror/68)
**Author:** [@NICOLAS\_IGNACIO\_BREV](https://opentps.discourse.group/u/NICOLAS_IGNACIO_BREV)\ **Replies:** 16\ **Last updated:** [July 10, 2025, 9:49am UTC](https://opentps.discourse.group/t/modulenotfounderror/68 "2025-07-10T09:49:58Z")
Hi, I’m new to OpenTPS and have been trying to run the examples in the repository on my computer. In this case, I ran the “photonPlanCreationAndDoseCalculation” example, but I’m getting this error. I installed it step by… --- ## [Download the PhD theses](https://opentps.discourse.group/t/download-the-phd-theses/78)
**Author:** [@STRE\_RING](https://opentps.discourse.group/u/STRE_RING)\ **Replies:** 4\ **Last updated:** [July 8, 2025, 6:31pm UTC](https://opentps.discourse.group/t/download-the-phd-theses/78 "2025-07-08T18:31:52Z")
Hi, I want to access the PhD theses, but they are not currently available on the website. Could you please give me some help? Thank you! Ke --- ## [CUDA, cupy, numpy and OpenTPS compatibility](https://opentps.discourse.group/t/cuda-cupy-numpy-and-opentps-compatibility/74)
**Author:** [@pawel](https://opentps.discourse.group/u/pawel)\ **Replies:** 4\ **Last updated:** [July 2, 2025, 10:50am UTC](https://opentps.discourse.group/t/cuda-cupy-numpy-and-opentps-compatibility/74 "2025-07-02T10:50:54Z")
Hello, I’m a new user of the OpenTPS software. My installation went fine, but when I ran opentps some warning messages started appearing. One was in regard with Gurobi package, if I’m not mistaken, and the other one r… [Next page](https://opentps.discourse.group/latest.md?page=1)