#!/usr/bin/env python3 from tabulate import AngleTabulate ################################################################################ import math def harmonic_energy(theta): k = 100.0 thetazero = 120.0 # the force constant in LAMMPS is in energy per radians^2 so convert from degrees to radians deg2rad = math.pi / 180.0 t = (theta - thetazero) * deg2rad f = k * t * t return f ################################################################################ if __name__ == "__main__": atable = AngleTabulate(harmonic_energy, units='real') atable.run('HARM')