cesaremalosso

Added examples for the computation of viscosity

LAMMPS fix dplr issue

6

### Summary `ERROR: find a bonded pair that is not on the same processor, something should not happen (../fix_dplr.cpp:345)` when restart from a previous simulation run. ### DeePMD-kit Version 2.2.3...

[Feature Request] Poor performance of ppm/dplr for long-range interactions

2

### Summary `kspace_style pppm/dplr` is quite slow in LAMMPS, significantly slowing down the MD simulation. A multiprocessing code running on CPU (or a GPU implementation) could speed-up significantly the simulation....