MacOS - fix SGCMC

Greetings All - I am working on MacOS and have installed the latest stable lammps via brew - version I have is 20220623 → june 23 2022;

Issue: I am trying to run fix sgcmc and this is what I get: ERROR: Unrecognized fix style ‘sgcmc’ (src/modify.cpp:903). I am assuming it is indicating that sgcmc is NOT part of the LAMMPS package that I have. I also searched my system - and am not able to find fix sgcmc within my 20220623 version. Just fyi, I have listed (below) the contents of the mc directory and it ONLY has fix gcmc.

I have seen an earlier message ( Windows MSMPI LAMMPS version 28 March 2023 ) from April that indicate sgcmc is indeed available with the mc package but for windows - can you please point me to the equivalent MacOs version?

Thanks a lot!
Khalid

/opt/homebrew/Cellar/lammps/20220623/share/lammps/examples/mc
(base) khalidmansour@khalids-MacBook-Pro mc % ls
CO2.txt data.widom.lj in.mixed log.03Mar22.gcmc.co2.g++.4 log.27Nov18.gcmc.h2o.g++.1 log.30Jun20.widom.lj.g++.4
H2O.txt in.gcmc.co2 in.pure log.03Mar22.gcmc.h2o.g++.4 log.27Nov18.gcmc.lj.g++.1 log.30Jun20.widom.spce.g++.1
data.bead in.gcmc.h2o in.widom.lj

The first line of the documentation of fix sgcmc says “New in version 22Dec2022”, so I would first re-try with a recent version of LAMMPS.

Simon

Hi Simon - Thanks for the reply. I figured that much before I posted my question. Please note that I un-installed lammps 5 times and re-installed and always picks up the june 23 2022 version!!!

I have just visited the site where brew picks up lammps Macos and to my surprise ONLY the 2022 LAMMPS versions are there - no 2023 versions - take a look below!

Perhaps you can, or (Axel or Steve) shed light on why is that?

Thanks again,
Khalid

list straight from brew mirrors site - it has 2023 versions for many packages but NOT for MACOS!

Index of /homebrew-bottles/ :

lacework-cli-1.27.0.arm64_big_sur.bottle.tar.gz
10-Jul-2023 20:12 12182149 lacework-cli-1.27.0.arm64_monterey.bottle.tar.gz 10-Jul-2023 20:12 12178202 lacework-cli-1.27.0.arm64_ventura.bottle.tar.gz 10-Jul-2023 20:11 12177853 lacework-cli-1.27.0.big_sur.bottle.tar.gz 10-Jul-2023 20:12 12783969 lacework-cli-1.27.0.monterey.bottle.tar.gz 10-Jul-2023 20:12 12783754 lacework-cli-1.27.0.ventura.bottle.tar.gz 10-Jul-2023 20:12 12782103 lacework-cli-1.27.0.x86_64_linux.bottle.tar.gz 10-Jul-2023 20:12 12135852 ladspa-sdk-1.17.x86_64_linux.bottle.1.tar.gz 05-Nov-2022 05:40 34590 lame-3.100.arm64_big_sur.bottle.tar.gz 07-Apr-2021 04:29 798531 lame-3.100.arm64_monterey.bottle.tar.gz 22-Oct-2021 02:51 799678 lame-3.100.arm64_ventura.bottle.tar.gz 22-Oct-2022 01:17 799260 lame-3.100.big_sur.bottle.tar.gz 07-Apr-2021 04:29 792110 lame-3.100.catalina.bottle.tar.gz 07-Apr-2021 04:29 792652 lame-3.100.el_capitan.bottle.tar.gz 07-Apr-2021 04:29 782382 lame-3.100.high_sierra.bottle.tar.gz 07-Apr-2021 04:29 777775 lame-3.100.mojave.bottle.tar.gz 07-Apr-2021 04:29 778983 lame-3.100.monterey.bottle.tar.gz 22-Oct-2021 03:04 798290 lame-3.100.sierra.bottle.tar.gz 07-Apr-2021 04:29 777773 lame-3.100.ventura.bottle.tar.gz 15-Nov-2022 07:47 795249 lame-3.100.x86_64_linux.bottle.tar.gz 06-Jul-2021 02:58 861905 lammps-**20220623.arm64_big_sur.bottle.tar.gz 01-Aug-2022 15:03 119856012 lammps-20220623.arm64_monterey.bottle.tar.gz 01-Aug-2022 15:03 119847463 lammps-20220623.arm64_ventura.bottle.tar.gz 27-Oct-2022 05:57 119885694 lammps-20220623.big_sur.bottle.tar.gz 01-Aug-2022 15:03 121609490 lammps-20220623.catalina.bottle.tar.gz 01-Aug-2022 15:03 121609729 lammps-20220623.monterey.bottle.tar.gz 01-Aug-2022 15:03 121618835 lammps-20220623.ventura.bottle.tar.gz 21-Nov-2022 10:09 121666188 [lammps-20220623.x86_64_linux.bottle.tar.gz](https://mirrors.xtom.ee/homebrew-bottles/lammps-**

Yes this is a common issue. Do not use brew if they are not up to date, compile your own LAMMPS version.

The primary distribution of the LAMMPS software is a tarball with source code.

All packaging of LAMMPS (i.e. LAMMPS for Ubuntu, Fedora, RedHat, SuSE, Conda, Pip, Homebrew, Gentoo, Arch, FreeBSD ports, Windows) is managed by the individual packagers.

With the exception of the Windows installer packages (which are built and maintained by me), all of those are not managed (and thus not under control) by LAMMPS developers. If you want support for different versions of LAMMPS than what is supported by the packaging, you need to contact the package maintainers and/or use the distribution project’s communication channels.

LAMMPS feature releases are fairly recent (every couple months or so), so many package maintainers choose to not update LAMMPS at the same frequency but rather follow the stable releases only (about once per year with multiple bugfix updates in between). In the latter case, you will need to wait until the next stable release (estimated within the next 6 weeks) and when the packaging folks notice the new release and find the time to package it. Please note that many people doing the packaging are volunteers (same as those responding in the forum here) are volunteers that do this in their spare time and for “fun”, so please treat them with respect. Without their efforts, there would be no convenience through packaging at all.

As @simongravelle pointed out, if you are not happy with the versions available through the packaging system, then you always have the option to compile LAMMPS from source yourself. If this was 10 years ago, compiling from source would have been your only option.

Thanks Axel and Simon. Lesson learned. LAMMPS is working as expected.
Best regards, K