Does "Develper guide" out of date?

Dear Dr. Axel Kohlmeyer and other users:
I want to program a new fix function, and I find a Developer Guide(https://lammps.sandia.gov/doc/Developer.pdf) on the home webpage of LAMMPS. It suggests that it was written in 2011. I want to ask whether this well-written out of time? And also, there is a section that explains how to extend LAMMPS in the manual(https://lammps.sandia.gov/doc/Modify.html). Which should I refer priority first?

This is the first time that I try to write codes to extend LAMMPS, so I would be grateful if you can give me a clear guide.

ps, I think my goal can not be achieved by functions available now.

Thanks in advance!

Roy Kid

Dear Dr. Axel Kohlmeyer and other users:
I want to program a new fix function, and I find a Developer Guide(https://lammps.sandia.gov/doc/Developer.pdf) on the home webpage of LAMMPS. It suggests that it was written in 2011. I want to ask whether this well-written out of time? And also, there is a section that explains how to extend LAMMPS in the manual(https://lammps.sandia.gov/doc/Modify.html). Which should I refer priority first?

the second. that one is kept (mostly) up-to-date. for specifics, you will still need to read source code, especially comments in the headers or comments in other code similar to what you want to do. LAMMPS is too big and some of the details are too specific to explain them all in detail in the documentation.

if you have further questions, another e-mail to this mailing list with more details and possibly explaining what you have already done would be the way to learn more.

This is the first time that I try to write codes to extend LAMMPS, so I would be grateful if you can give me a clear guide.

ps, I think my goal can not be achieved by functions available now.

nobody can tell you unless you explain with sufficient detail what you want to do.

axel.