From users at einsteintoolkit.org Wed Jul 1 17:15:01 2026 From: users at einsteintoolkit.org (users at einsteintoolkit.org) Date: Wed, 01 Jul 2026 17:15:01 -0500 Subject: [Users] Einstein Toolkit Meeting Reminder Message-ID: <6a459165.CcVIla81JYhEgHrr%users@einsteintoolkit.org> Hello, Please consider joining the weekly Einstein Toolkit phone call at 9:00 am US central time on Thursdays. For details on how to connect and what agenda items are to be discussed, use the link below. https://docs.einsteintoolkit.org/et-docs/Main_Page#Weekly_Users_Call --The Maintainers From makino.taiki.g6 at s.mail.nagoya-u.ac.jp Wed Jul 1 18:39:00 2026 From: makino.taiki.g6 at s.mail.nagoya-u.ac.jp (MAKINO Taiki) Date: Wed, 1 Jul 2026 23:39:00 +0000 Subject: [Users] Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction Message-ID: Dear Einstein Toolkit Users, I am a new Einstein Toolkit user, and I have some questions about a BNS simulation. I am trying to run a BNS simulation using bns.par, which I downloaded from Einstein Toolkit Gallery (https://einsteintoolkit.org/gallery/bns/index.html) and slightly modified. I can successfully create and submit the simulation but the following message appears during the simulation: INFO (IllinoisGRMHD): C2P: Iter. # 0, Lev: 5 NumPts= 132300 | Backups: 0 0 0 | Fixes: VL= 0 rho*= 0 Averaged pts = 38250 Font1D 38250 | Failures: 2250 InHoriz= 0 / 0 | 1.00 iters/gridpt Error, Sum: rho 6.378e-08, 2.433e-05 | tau nan, -nan | Sx nan, nan | Sy nan, nan | Sz nan, nan To investigate this problem, I added the following parameters: Multipole::interpolator_name = "Lagrange polynomial interpolation" Multipole::interpolator_pars = "order=4" I also changed the parameter Driver::ghost_size from 3 to 4, but the same error occurred. I would like to ask: * What could cause tau, Sx, Sy, and Sz to become NaN in this situation? * Does this indicate a failure of C2P conversion? * Are there any parameter settings or initial data that I should check first? Additionally, I have another question. When I use kuibit to extract Psi4, I expected to obtain the full time series (or all available modes) but the returned object contains only one element, for example, ??????SimDir.gws[100][(2,2)].y=[-9.79586237e-15-5.27476073e-14j]. Other attributes such as ?????? SimDir.gws[100][(2,2)].x also contain only one element. Is this a correct behavior or could it indicate a problem with my .par file? For reference, I have attached my parameter file. Thank you very much for your time and any suggestions. Best regards, Taiki Makino Graduate School of Science, Nagoya University makino.taiki.g6 at s.mail.nagoya-u.ac.jp ?? Outlook for Mac ?? Outlook for Mac -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: bns.par Type: application/octet-stream Size: 22972 bytes Desc: bns.par URL: From jnicoules at ua.pt Thu Jul 2 05:31:14 2026 From: jnicoules at ua.pt (Jordan Nicoules) Date: Thu, 2 Jul 2026 10:31:14 +0000 Subject: [Users] Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction In-Reply-To: References: Message-ID: <1b6df6af29a246db89624283275d1549@ua.pt> Hi Taiko, I will (partly) skip the first part of your message and let others reply on that, as I don't have experience with NS simulations. Regarding the gravitational wave extraction, I think you are accessing the data correctly (your example gives the time series for one mode at one radius), and there should be more than one element in general. From your parameter file, it seems the output should go to an ascii file (it's the default), so you can double check in that file too. However, since you have `Multipole::out_every = 128`, does your simulation reach iteration 128 and later? In particular, because you're getting nans at iteration 0, does the simulation actually go past t=0? Given what you're saying, I guess your single element of `SimDir.gws[100][(2,2)].x` is 0 (i.e t=0). Best, Jordan ________________________________ From: Users on behalf of MAKINO Taiki via Users Sent: Thursday, July 2, 2026 12:39:00 AM To: users at einsteintoolkit.org Subject: [Users] Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction CUIDADO: Email de um sistema externo. Cuidado com links, anexos e pedidos de dados/senhas. CAUTION: Email from an external system. Be careful with links, attachments, and requests for data/passwords. Dear Einstein Toolkit Users, I am a new Einstein Toolkit user, and I have some questions about a BNS simulation. I am trying to run a BNS simulation using bns.par, which I downloaded from Einstein Toolkit Gallery (https://einsteintoolkit.org/gallery/bns/index.html) and slightly modified. I can successfully create and submit the simulation but the following message appears during the simulation: INFO (IllinoisGRMHD): C2P: Iter. # 0, Lev: 5 NumPts= 132300 | Backups: 0 0 0 | Fixes: VL= 0 rho*= 0 Averaged pts = 38250 Font1D 38250 | Failures: 2250 InHoriz= 0 / 0 | 1.00 iters/gridpt Error, Sum: rho 6.378e-08, 2.433e-05 | tau nan, -nan | Sx nan, nan | Sy nan, nan | Sz nan, nan To investigate this problem, I added the following parameters: Multipole::interpolator_name = "Lagrange polynomial interpolation" Multipole::interpolator_pars = "order=4" I also changed the parameter Driver::ghost_size from 3 to 4, but the same error occurred. I would like to ask: * What could cause tau, Sx, Sy, and Sz to become NaN in this situation? * Does this indicate a failure of C2P conversion? * Are there any parameter settings or initial data that I should check first? Additionally, I have another question. When I use kuibit to extract Psi4, I expected to obtain the full time series (or all available modes) but the returned object contains only one element, for example, ??????SimDir.gws[100][(2,2)].y=[-9.79586237e-15-5.27476073e-14j]. Other attributes such as ?????? SimDir.gws[100][(2,2)].x also contain only one element. Is this a correct behavior or could it indicate a problem with my .par file? For reference, I have attached my parameter file. Thank you very much for your time and any suggestions. Best regards, Taiki Makino Graduate School of Science, Nagoya University makino.taiki.g6 at s.mail.nagoya-u.ac.jp ?? Outlook for Mac ?? Outlook for Mac -------------- next part -------------- An HTML attachment was scrubbed... URL: From rhaas at mail.ubc.ca Thu Jul 2 10:09:40 2026 From: rhaas at mail.ubc.ca (Roland Haas) Date: Thu, 2 Jul 2026 08:09:40 -0700 Subject: [Users] meeting minutes for 2026-07-02 Message-ID: <20260702080940.2083f116@haengie2.phas.ubc.ca> Present: Roland, Steve, Peter, Deborah, Lucas, Maxwell, Zach, Cheng-Hsin, Yosef Chair: Zach Minutes: Roland ET release ========== * BBH gallery example test for code changes: no update yet * TwoPuncturesX: no vote yet * Steve working on acceptance emails * Stampede 3 is still being worked on, Steve will try and help out * there is an outstanding pull request for Delta that is needed after a recent update, Cheng-Hsin and Roland to coordinate * Lucas / Steve will set up on Expanse and run the testsuite * Peter re-ran tests on sunrise, 3 remaining failures * Steve found that changes are needed to compiled on Fedora and QueenBee ** will report back, likely not before the release Tickets transition to GitHub ============================ * will get started next week, Zach and Roland are signed up Code transition to GitHub ========================= * no update * Zach would like to reach out to people who self-host to move thorns into ET owned repos, especially for bitbucket repos SPEC inclusion ============== * Steve and Roland had to get back to SPEC team about performance Unanswered questions ==================== * Abderrahim El Khou is looking for collaborations to learn how to use ET: http://lists.einsteintoolkit.org/pipermail/users/2026-June/009972.html Yours, Roland -- My email is as private as my paper mail. I therefore support encrypting and signing email messages. Get my PGP key from http://pgp.mit.edu . From hwitek at illinois.edu Thu Jul 2 14:47:34 2026 From: hwitek at illinois.edu (Helvi Witek) Date: Thu, 2 Jul 2026 14:47:34 -0500 Subject: [Users] number of thesis using the Einstein Toolkit Message-ID: Dear all, for a report to the National Science Foundation (NSF) I am trying to obtain an idea of how many student thesis were using (whether in progress or submitted) the Einstein Toolkit or CarpetX. So if you are a student or are working with a student and have *used the Einstein Toolkit or CarpetX as part of your thesis work* *between 1 August 2025 and 31 July 2026* it would be great if you could let me know *by 10 July 2026*? (ideally also incl. the degree obtained / program type). Best wishes Helvi --------------------------------------------- Dr. Helvi Witek Associate Professor Department of Physics University of Illinois at Urbana-Champaign 247 Loomis Lab 1110 W Green St Urbana, IL 61801 --------------------------------------------- -------------- next part -------------- An HTML attachment was scrubbed... URL: From makino.taiki.g6 at s.mail.nagoya-u.ac.jp Fri Jul 3 04:14:57 2026 From: makino.taiki.g6 at s.mail.nagoya-u.ac.jp (MAKINO Taiki) Date: Fri, 3 Jul 2026 09:14:57 +0000 Subject: [Users] Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction In-Reply-To: <1b6df6af29a246db89624283275d1549@ua.pt> References: <1b6df6af29a246db89624283275d1549@ua.pt> Message-ID: Dear Jordan Thank you for your response. When I checked the result of my simulation, SimDir.gws[100][(2,2)].x was indeed 0 as you said and the simulation stopped at iteration=0. Also, I checked the psi4 ASCII files and all of them contained only one line. (However, the ASCII files that do not contain information of psi4 have several lines of data.) I am not sure what is causing this. What should I do next ? Best regards, Taiki Makino Graduate School of Science, Nagoya University makino.taiki.g6 at s.mail.nagoya-u.ac.jp ?? Outlook for Mac ???: Jordan Nicoules ??: ???, 2026?7?2? 19:31 ??: MAKINO Taiki ; users at einsteintoolkit.org ??: Re: Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction Hi Taiko, I will (partly) skip the first part of your message and let others reply on that, as I don't have experience with NS simulations. Regarding the gravitational wave extraction, I think you are accessing the data correctly (your example gives the time series for one mode at one radius), and there should be more than one element in general. From your parameter file, it seems the output should go to an ascii file (it's the default), so you can double check in that file too. However, since you have `Multipole::out_every = 128`, does your simulation reach iteration 128 and later? In particular, because you're getting nans at iteration 0, does the simulation actually go past t=0? Given what you're saying, I guess your single element of `SimDir.gws[100][(2,2)].x` is 0 (i.e t=0). Best, Jordan ________________________________ From: Users on behalf of MAKINO Taiki via Users Sent: Thursday, July 2, 2026 12:39:00 AM To: users at einsteintoolkit.org Subject: [Users] Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction CUIDADO: Email de um sistema externo. Cuidado com links, anexos e pedidos de dados/senhas. CAUTION: Email from an external system. Be careful with links, attachments, and requests for data/passwords. Dear Einstein Toolkit Users, I am a new Einstein Toolkit user, and I have some questions about a BNS simulation. I am trying to run a BNS simulation using bns.par, which I downloaded from Einstein Toolkit Gallery (https://einsteintoolkit.org/gallery/bns/index.html) and slightly modified. I can successfully create and submit the simulation but the following message appears during the simulation: INFO (IllinoisGRMHD): C2P: Iter. # 0, Lev: 5 NumPts= 132300 | Backups: 0 0 0 | Fixes: VL= 0 rho*= 0 Averaged pts = 38250 Font1D 38250 | Failures: 2250 InHoriz= 0 / 0 | 1.00 iters/gridpt Error, Sum: rho 6.378e-08, 2.433e-05 | tau nan, -nan | Sx nan, nan | Sy nan, nan | Sz nan, nan To investigate this problem, I added the following parameters: Multipole::interpolator_name = "Lagrange polynomial interpolation" Multipole::interpolator_pars = "order=4" I also changed the parameter Driver::ghost_size from 3 to 4, but the same error occurred. I would like to ask: * What could cause tau, Sx, Sy, and Sz to become NaN in this situation? * Does this indicate a failure of C2P conversion? * Are there any parameter settings or initial data that I should check first? Additionally, I have another question. When I use kuibit to extract Psi4, I expected to obtain the full time series (or all available modes) but the returned object contains only one element, for example, ??????SimDir.gws[100][(2,2)].y=[-9.79586237e-15-5.27476073e-14j]. Other attributes such as ?????? SimDir.gws[100][(2,2)].x also contain only one element. Is this a correct behavior or could it indicate a problem with my .par file? For reference, I have attached my parameter file. Thank you very much for your time and any suggestions. Best regards, Taiki Makino Graduate School of Science, Nagoya University makino.taiki.g6 at s.mail.nagoya-u.ac.jp ?? Outlook for Mac ?? Outlook for Mac -------------- next part -------------- An HTML attachment was scrubbed... URL: From jnicoules at ua.pt Fri Jul 3 04:37:46 2026 From: jnicoules at ua.pt (Jordan Nicoules) Date: Fri, 3 Jul 2026 09:37:46 +0000 Subject: [Users] Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction In-Reply-To: References: <1b6df6af29a246db89624283275d1549@ua.pt>, Message-ID: <4320d3b118924d7293f42b5915a79a71@ua.pt> Hi Taiki, (apologies for my previous typo) The next step would be to understand why the simulation crashes and doesn't go past t=0. This is beyond what I can quickly hotfix I think, so I'm calling to other members to answer that. Potentially, if you have the chance, the weekly calls can also be an opportunity to interact with people directly and put forth your questions. Regarding files that have more than one line of data, that would make sense for the 1D profiles, but they still probably only correspond to iteration 0 (t=0). Best, Jordan ________________________________ From: MAKINO Taiki Sent: Friday, July 3, 2026 10:14:57 AM To: Jordan Nicoules Cc: users at einsteintoolkit.org Subject: Re: Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction CUIDADO: Email de um sistema externo. Cuidado com links, anexos e pedidos de dados/senhas. CAUTION: Email from an external system. Be careful with links, attachments, and requests for data/passwords. Dear Jordan Thank you for your response. When I checked the result of my simulation, SimDir.gws[100][(2,2)].x was indeed 0 as you said and the simulation stopped at iteration=0. Also, I checked the psi4 ASCII files and all of them contained only one line. (However, the ASCII files that do not contain information of psi4 have several lines of data.) I am not sure what is causing this. What should I do next ? Best regards, Taiki Makino Graduate School of Science, Nagoya University makino.taiki.g6 at s.mail.nagoya-u.ac.jp ?? Outlook for Mac ???: Jordan Nicoules ??: ???, 2026?7?2? 19:31 ??: MAKINO Taiki ; users at einsteintoolkit.org ??: Re: Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction Hi Taiko, I will (partly) skip the first part of your message and let others reply on that, as I don't have experience with NS simulations. Regarding the gravitational wave extraction, I think you are accessing the data correctly (your example gives the time series for one mode at one radius), and there should be more than one element in general. From your parameter file, it seems the output should go to an ascii file (it's the default), so you can double check in that file too. However, since you have `Multipole::out_every = 128`, does your simulation reach iteration 128 and later? In particular, because you're getting nans at iteration 0, does the simulation actually go past t=0? Given what you're saying, I guess your single element of `SimDir.gws[100][(2,2)].x` is 0 (i.e t=0). Best, Jordan ________________________________ From: Users on behalf of MAKINO Taiki via Users Sent: Thursday, July 2, 2026 12:39:00 AM To: users at einsteintoolkit.org Subject: [Users] Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction CUIDADO: Email de um sistema externo. Cuidado com links, anexos e pedidos de dados/senhas. CAUTION: Email from an external system. Be careful with links, attachments, and requests for data/passwords. Dear Einstein Toolkit Users, I am a new Einstein Toolkit user, and I have some questions about a BNS simulation. I am trying to run a BNS simulation using bns.par, which I downloaded from Einstein Toolkit Gallery (https://einsteintoolkit.org/gallery/bns/index.html) and slightly modified. I can successfully create and submit the simulation but the following message appears during the simulation: INFO (IllinoisGRMHD): C2P: Iter. # 0, Lev: 5 NumPts= 132300 | Backups: 0 0 0 | Fixes: VL= 0 rho*= 0 Averaged pts = 38250 Font1D 38250 | Failures: 2250 InHoriz= 0 / 0 | 1.00 iters/gridpt Error, Sum: rho 6.378e-08, 2.433e-05 | tau nan, -nan | Sx nan, nan | Sy nan, nan | Sz nan, nan To investigate this problem, I added the following parameters: Multipole::interpolator_name = "Lagrange polynomial interpolation" Multipole::interpolator_pars = "order=4" I also changed the parameter Driver::ghost_size from 3 to 4, but the same error occurred. I would like to ask: * What could cause tau, Sx, Sy, and Sz to become NaN in this situation? * Does this indicate a failure of C2P conversion? * Are there any parameter settings or initial data that I should check first? Additionally, I have another question. When I use kuibit to extract Psi4, I expected to obtain the full time series (or all available modes) but the returned object contains only one element, for example, ??????SimDir.gws[100][(2,2)].y=[-9.79586237e-15-5.27476073e-14j]. Other attributes such as ?????? SimDir.gws[100][(2,2)].x also contain only one element. Is this a correct behavior or could it indicate a problem with my .par file? For reference, I have attached my parameter file. Thank you very much for your time and any suggestions. Best regards, Taiki Makino Graduate School of Science, Nagoya University makino.taiki.g6 at s.mail.nagoya-u.ac.jp ?? Outlook for Mac ?? Outlook for Mac -------------- next part -------------- An HTML attachment was scrubbed... URL: From makino.taiki.g6 at s.mail.nagoya-u.ac.jp Fri Jul 3 05:10:37 2026 From: makino.taiki.g6 at s.mail.nagoya-u.ac.jp (MAKINO Taiki) Date: Fri, 3 Jul 2026 10:10:37 +0000 Subject: [Users] Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction In-Reply-To: <4320d3b118924d7293f42b5915a79a71@ua.pt> References: <1b6df6af29a246db89624283275d1549@ua.pt>, <4320d3b118924d7293f42b5915a79a71@ua.pt> Message-ID: Dear Jordan Thank you for your quick response. I understand what I should do. I will wait for feedback from the others, and I consider attending the weekly meeting. Thank you again for your advice. Best regards, Taiki Makino Graduate School of Science, Nagoya University makino.taiki.g6 at s.mail.nagoya-u.ac.jp ?? Outlook for Mac ???: Jordan Nicoules ??: ???, 2026?7?3? 18:38 ??: MAKINO Taiki CC: users at einsteintoolkit.org ??: Re: Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction Hi Taiki, (apologies for my previous typo) The next step would be to understand why the simulation crashes and doesn't go past t=0. This is beyond what I can quickly hotfix I think, so I'm calling to other members to answer that. Potentially, if you have the chance, the weekly calls can also be an opportunity to interact with people directly and put forth your questions. Regarding files that have more than one line of data, that would make sense for the 1D profiles, but they still probably only correspond to iteration 0 (t=0). Best, Jordan ________________________________ From: MAKINO Taiki Sent: Friday, July 3, 2026 10:14:57 AM To: Jordan Nicoules Cc: users at einsteintoolkit.org Subject: Re: Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction CUIDADO: Email de um sistema externo. Cuidado com links, anexos e pedidos de dados/senhas. CAUTION: Email from an external system. Be careful with links, attachments, and requests for data/passwords. Dear Jordan Thank you for your response. When I checked the result of my simulation, SimDir.gws[100][(2,2)].x was indeed 0 as you said and the simulation stopped at iteration=0. Also, I checked the psi4 ASCII files and all of them contained only one line. (However, the ASCII files that do not contain information of psi4 have several lines of data.) I am not sure what is causing this. What should I do next ? Best regards, Taiki Makino Graduate School of Science, Nagoya University makino.taiki.g6 at s.mail.nagoya-u.ac.jp ?? Outlook for Mac ???: Jordan Nicoules ??: ???, 2026?7?2? 19:31 ??: MAKINO Taiki ; users at einsteintoolkit.org ??: Re: Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction Hi Taiko, I will (partly) skip the first part of your message and let others reply on that, as I don't have experience with NS simulations. Regarding the gravitational wave extraction, I think you are accessing the data correctly (your example gives the time series for one mode at one radius), and there should be more than one element in general. From your parameter file, it seems the output should go to an ascii file (it's the default), so you can double check in that file too. However, since you have `Multipole::out_every = 128`, does your simulation reach iteration 128 and later? In particular, because you're getting nans at iteration 0, does the simulation actually go past t=0? Given what you're saying, I guess your single element of `SimDir.gws[100][(2,2)].x` is 0 (i.e t=0). Best, Jordan ________________________________ From: Users on behalf of MAKINO Taiki via Users Sent: Thursday, July 2, 2026 12:39:00 AM To: users at einsteintoolkit.org Subject: [Users] Question about IllinoisGRMHD C2P failure and kuibit Psi4 extraction CUIDADO: Email de um sistema externo. Cuidado com links, anexos e pedidos de dados/senhas. CAUTION: Email from an external system. Be careful with links, attachments, and requests for data/passwords. Dear Einstein Toolkit Users, I am a new Einstein Toolkit user, and I have some questions about a BNS simulation. I am trying to run a BNS simulation using bns.par, which I downloaded from Einstein Toolkit Gallery (https://einsteintoolkit.org/gallery/bns/index.html) and slightly modified. I can successfully create and submit the simulation but the following message appears during the simulation: INFO (IllinoisGRMHD): C2P: Iter. # 0, Lev: 5 NumPts= 132300 | Backups: 0 0 0 | Fixes: VL= 0 rho*= 0 Averaged pts = 38250 Font1D 38250 | Failures: 2250 InHoriz= 0 / 0 | 1.00 iters/gridpt Error, Sum: rho 6.378e-08, 2.433e-05 | tau nan, -nan | Sx nan, nan | Sy nan, nan | Sz nan, nan To investigate this problem, I added the following parameters: Multipole::interpolator_name = "Lagrange polynomial interpolation" Multipole::interpolator_pars = "order=4" I also changed the parameter Driver::ghost_size from 3 to 4, but the same error occurred. I would like to ask: * What could cause tau, Sx, Sy, and Sz to become NaN in this situation? * Does this indicate a failure of C2P conversion? * Are there any parameter settings or initial data that I should check first? Additionally, I have another question. When I use kuibit to extract Psi4, I expected to obtain the full time series (or all available modes) but the returned object contains only one element, for example, ??????SimDir.gws[100][(2,2)].y=[-9.79586237e-15-5.27476073e-14j]. Other attributes such as ?????? SimDir.gws[100][(2,2)].x also contain only one element. Is this a correct behavior or could it indicate a problem with my .par file? For reference, I have attached my parameter file. Thank you very much for your time and any suggestions. Best regards, Taiki Makino Graduate School of Science, Nagoya University makino.taiki.g6 at s.mail.nagoya-u.ac.jp ?? Outlook for Mac ?? Outlook for Mac -------------- next part -------------- An HTML attachment was scrubbed... URL: From nils.vu at black-holes.org Sat Jul 4 17:55:18 2026 From: nils.vu at black-holes.org (Nils Vu) Date: Sun, 5 Jul 2026 00:55:18 +0200 Subject: [Users] [nr-community-call] Next NR community call: Monday, Jul 6 Message-ID: Dear Numerical Relativists, Our next NR community call will be on Monday, Jul 6 (9am Pacific, noon NYC, 6pm Berlin). Our speaker will be Stamatis Vretinaris (IMAPP Radboud & AEI). You can find the schedule in the wiki: https://github.com/sxs-collaboration/nr-community-call/wiki As always: - Feel free to circulate this information within the NR community. - Please subscribe to our mailing list to receive info on the community calls in the future (or send a short message to nr-community-call+subscribe at black-holes.org to subscribe) and join our Slack for discussions (channel: #nr-community-call ). - Please sign up for a slot in the schedule to speak at one of the community calls: https://github.com/sxs-collaboration/nr-community-call/wiki Best, Nils ? Nils Vu (he/him) SNSF Ambizione Fellow University of Zurich To unsubscribe from this group and stop receiving emails from it, send an email to nr-community-call+unsubscribe at black-holes.org. -------------- next part -------------- An HTML attachment was scrubbed... URL: From users at einsteintoolkit.org Mon Jul 6 15:18:01 2026 From: users at einsteintoolkit.org (users at einsteintoolkit.org) Date: Mon, 06 Jul 2026 15:18:01 -0500 Subject: [Users] Agenda for Thursday's Meeting Message-ID: <6a4c0d79.VE0Fzkt3xrpMKc9x%users@einsteintoolkit.org> Please update the Wiki with agenda items for Thursday's meeting. Thanks! https://docs.einsteintoolkit.org/et-docs/meeting_agenda --The Maintainers From jnicoules at ua.pt Tue Jul 7 12:20:51 2026 From: jnicoules at ua.pt (Jordan Nicoules) Date: Tue, 7 Jul 2026 17:20:51 +0000 Subject: [Users] Bug in CarpetRegrid2 (revealing a deeper issue?) Message-ID: <7680295e649d434e89afc940fdf3677c@ua.pt> Dear all, A couple of weeks ago, I found out that there was a bug in CarpetRegrid2. Namely, it does not properly check for a change of radius of the refinement levels (when they are steered by a Trigger for instance). Looking a bit closer, it seems that the computed `drfac` in `CarpetRegrid2/src/regrid.cc` is nan, and thus `do_recompose` is not set to true. In particular, it means it is possible to change the radii if something else triggers a regridding (for instance, changing the number of active levels). However, while I was trying to understand and fix this bug, it appeared there might be a deeper issue. I'm struggling to understand if it may be related to memory, compilation, ... It would be helpful if any of you had some insight to share, or could try to replicate the issue. To that effect, I'm attaching a minimal parfile adapted from CarpetRegrid2/test/regrid2_granularity.par, as well as a modified regrid.cc file that should allow you to reproduce the situation. More details on the situation below. Best, Jordan ---------------------------- ----- More details ----- ---------------------------- To figure out why drfac is nan, I added manual debugging information prints in the code. Depending on what information I ask, and in what order, I don't get consistent nor sensible results. I'm reaching out here first instead of opening a ticket because I can't pinpoint the precise issue. I haven't tried different compilers (I have gcc 11.4.0 locally), but this is happening even with a debug build (see attached make.config.defn file). More precisely, printing `rad`, `oldrad`, `rad - oldrad` is fine (done through std::cout). Printing (CCTK_VINFO) the numerator and denominator of `drfac` separately gives the right values for them, but the quotient `drfac` is wrong (it is 0, and not nan anymore, even when it shouldn't). If I create new local variables ``` CCTK_REAL const num = sqrt(sum(ipow(rad - oldrad, 2))); CCTK_REAL const den = sqrt(sum(ipow(oldrad, 2))); ``` and print them, they both contain the same value. It looks like the values are as if it uses rad=0 and whatever oldrad used to have before (which can be thus changed, depending on the order of the print lines). Finally, if I do print a lot of other info (in particular the intermediate computation steps), it seems it finally gets drfac right. I had a look at CarpetLib's vect.hh and defs.hh too, but I can't seem to understand what is going on. Note that there might be another small bug in the thorn, but fixing that didn't impact what I'm describing. I'm just attaching the other modified files (schedule.ccl and initialise.cc) for completeness, as it may lead to a fix eventually. -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: make.config.defn Type: application/octet-stream Size: 9506 bytes Desc: make.config.defn URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: regrid2_steer_radius.par Type: application/octet-stream Size: 2899 bytes Desc: regrid2_steer_radius.par URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: schedule.ccl Type: application/octet-stream Size: 624 bytes Desc: schedule.ccl URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: initialise.cc Type: text/x-c++src Size: 2946 bytes Desc: initialise.cc URL: -------------- next part -------------- A non-text attachment was scrubbed... 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