Hi Haining,

Hi Ray,

I want rotate an atom randomly around the other using 'displace_atoms

rotate' command. So random numbers need to be generated to define a vector

(three real numbers ranging from -INF to INF) and an angle in degree with

the range from 0 to 360.

Well, the displace_atoms random keyword takes 4 arguments and the

rotate keyword takes 7. Either does not match your description above.

Please see: LAMMPS Molecular Dynamics Simulator

But so far, after using 'variable equal random', it seems that all the

alignments are similar, not randomly generated.

The random function in variable takes 3 arguments. Please see:

What I am wondering is what is the proper way to generate random number in

LAMMPS using 'variable equal random' and how to set seeds? How seeds affect

random number generated?

This is a good start: Random seed - Wikipedia

Ray