import numpy as np
from pysisyphus.helpers import fit_rigid
from pysisyphus.optimizers.Optimizer import Optimizer
[docs]class QuickMin(Optimizer):
def __init__(self, geometry, dt=0.35, **kwargs):
super(QuickMin, self).__init__(geometry, **kwargs)
self.dt = dt
def _get_opt_restart_info(self):
opt_restart_info = {
"velocity": self.velocities[-1].tolist(),
}
return opt_restart_info
def _set_opt_restart_info(self, opt_restart_info):
velocity = np.array(opt_restart_info["velocity"], dtype=float)
self.velocities = [velocity, ]
[docs] def prepare_opt(self):
self.velocities = [np.zeros_like(self.geometry.coords), ]
[docs] def reset(self):
if self.coords[-1].size != self.coords[-2].size:
self.log("Number of coordinates changed. Adapting velocity vector "
"to new coordinate number.")
self.prepare_opt()
self.log("Resetted optimizer")
[docs] def optimize(self):
if self.align and self.is_cos:
(self.velocities[-1], ), _, _ = fit_rigid(self.geometry,
(self.velocities[-1], ))
prev_velocities = self.velocities[-1]
cur_forces = self.geometry.forces
self.forces.append(cur_forces)
self.energies.append(self.geometry.energy)
norm = np.linalg.norm(cur_forces)
if not self.is_cos:
self.log(f"Current energy={self.energies[-1]:.6f}")
self.log(f"norm(forces)={norm:.6f}")
if self.cur_cycle == 0:
tmp_velocities = np.zeros_like(prev_velocities)
else:
overlap = prev_velocities.dot(cur_forces)
self.log(f"Overlap of previous and current forces: {overlap:.6f}")
if overlap > 0:
tmp_velocities = (overlap * cur_forces
/ cur_forces.dot(cur_forces))
else:
tmp_velocities = np.zeros_like(prev_velocities)
self.log("Zeroed velocities")
accelerations = cur_forces / self.geometry.masses_rep
cur_velocities = tmp_velocities + self.dt*accelerations
steps = cur_velocities*self.dt + 1/2*accelerations*self.dt**2
steps = self.scale_by_max_step(steps)
self.velocities.append(cur_velocities)
velo_norm = np.linalg.norm(cur_velocities)
acc_norm = np.linalg.norm(accelerations)
self.log(f"norm(v) = {velo_norm:.4f}, norm(a) = {acc_norm:.4f}")
return steps