[gmx-developers] Modifying sim_util.c

[gleb solomentsev]

Hi,

Im working on modifying the calc_f_el subroutine to include a time 
varying electromagnetic field. The magnetic field component requires me 
to pass velocity values to this routine. As I understand this requires 
me to modify the main do_force routine call to also require velocity 
values to be passed to it. I have tried to do this but am finding that I 
have to modify a lot of other source files and calls to certain 
commands, for instance in the minimize.c routine.

It has been suggested to me by my coworker to make a separate header 
file to contain a copy of the particle velocities (ie global velocity 
copies) and to pass these copied velocities to the calc_f_el routine 
instead. He suggested that this would be a bit more simple and would 
limit the number of modifications I would have to make with a future 
release of gromacs.

I am wondering if you can make a suggestion as to how best to proceed at 
this point.

Thanks in advance,
Gleb