Dear Steve and users,

I am planning to port some of my subroutines (in Fortran) for computing the normal mode decomposition to Lammps and I would like your advise. These are really expensive computations that require the following:

- Read large input data sets involving complex numbers at the beginning of the run
- Initial atom positions should be stored
- Perform calculations involving complex numbers
- Parallel exchange of information on relatively small arrays
- Print large data sets (> 1-4GBs)
- Calculations should be performed every 8-16 time steps and only one call is required per step

I was thinking that both fix or input script commands could be suitable to do these calculations, any suggestion?

Regards, Javier