python/src/rwsims/sims.py

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2024-06-19 17:10:49 +00:00
from __future__ import annotations
from time import time
import numpy as np
from numpy.random import Generator
from scipy.interpolate import interp1d
from scipy.optimize import curve_fit
import matplotlib.pyplot as plt
from parameter import Parameter
from parser import parse
def ste(x, a, f_infty, tau, beta):
return a*((1-f_infty) * np.exp(-(x/tau)**beta) + f_infty)
def run_spectrum_sim(config_file: str):
p = parse(config_file)
rng, num_traj, t_max, delta, eta, num_variables = _prepare_sim(p)
num_echos = len(p.spec.t_echo)
reduction_factor = np.zeros((num_variables, num_echos))
freq = np.fft.fftshift(np.fft.fftfreq(p.spec.num_points, p.spec.dwell_time))
t_echo = p.spec.t_echo
t_echo_strings = list(map(str, t_echo))
# outer loop over variables of distribution of correlation times
for (i, dist_values) in enumerate(p.dist):
# noinspection PyCallingNonCallable
dist = p.dist.dist_type(**dist_values, rng=rng)
print(f'\nStart of {dist}')
chunks = int(0.6 * t_max / dist_values.get('tau', 1)) + 1
# second loop over parameter of motional model
for (j, motion_values) in enumerate(p.motion):
# noinspection PyCallingNonCallable
motion = p.motion.model(delta, eta, **motion_values, rng=rng)
print(f'Start of {motion}')
print(f'Simulate in chunks of {chunks}')
timesignal = np.zeros((p.spec.num_points, num_echos))
start = time()
# inner loop to create trajectories
for n in range(num_traj):
phase_interpol = make_trajectory(chunks, dist, motion, t_max)
for (k, t_echo_k) in enumerate(t_echo):
# effect of de-phasing and re-phasing
start_amp = -2 * phase_interpol(t_echo_k)
# start of actual acquisition
timesignal[:, k] += np.cos(start_amp + phase_interpol(p.spec.t_acq + 2 * t_echo_k)) * p.spec.dampening
reduction_factor[max(p.motion.num_variables, 1)*i + j, k] += np.cos(phase_interpol(2 * t_echo_k) + start_amp)
print_step(n, num_traj, start)
timesignal /= num_traj
# FT to spectrum
spec = np.fft.fftshift(np.fft.fft(timesignal, axis=0), axes=0).real
spec -= spec[0]
# plot spectra
fig, ax = plt.subplots()
lines = ax.plot(freq, spec)
ax.set_title(f'{dist}, {motion}')
ax.legend(lines, t_echo_strings)
fig2, ax2 = plt.subplots()
ax2.semilogx(p.dist.variables['tau'], reduction_factor/num_traj, 'o--')
plt.show()
def run_ste_sim(config_file: str):
p = parse(config_file)
rng, num_traj, t_max, delta, eta, num_variables = _prepare_sim(p)
cc = np.zeros((len(p.ste.t_mix), num_variables, len(p.ste.t_evo)))
ss = np.zeros((len(p.ste.t_mix), num_variables, len(p.ste.t_evo)))
# outer loop over variables of distribution of correlation times
for (i, dist_values) in enumerate(p.dist):
# noinspection PyCallingNonCallable
dist = p.dist.dist_type(**dist_values, rng=rng)
print(f'\nStart of {dist}')
chunks = int(0.6 * t_max / dist_values.get('tau', 1)) + 1
# second loop over parameter of motional model
for (j, motion_values) in enumerate(p.motion):
# noinspection PyCallingNonCallable
motion = p.motion.model(delta, eta, **motion_values, rng=rng)
print(f'Start of {motion}')
print(f'Simulate in chunks of {chunks}')
start = time()
# inner loop to create trajectories
for n in range(num_traj):
phase_interpol = make_trajectory(chunks, dist, motion, t_max)
for (k, t_evo_k) in enumerate(p.ste.t_evo):
dephased = phase_interpol(t_evo_k)
rephased = phase_interpol(p.ste.t_mix + 2*t_evo_k)-phase_interpol(p.ste.t_mix+t_evo_k)
cc[:, max(p.motion.num_variables, 1)*i + j, k] += np.cos(dephased)*np.cos(rephased)
ss[:, max(p.motion.num_variables, 1)*i + j, k] += np.sin(dephased)*np.sin(rephased)
print_step(n, num_traj, start)
cc /= num_traj
ss /= num_traj
fig, ax = plt.subplots()
fig2, ax2 = plt.subplots()
fig5, ax5 = plt.subplots()
fig3, ax3 = plt.subplots()
fig4, ax4 = plt.subplots()
for j in range(num_variables):
p0 = [0.5, 0, 1e-2, 1]
ax3.plot(p.ste.t_evo, cc[0, j, :])
ax3.plot(p.ste.t_evo, ss[0, j, :])
ax4.plot(p.ste.t_evo, cc[-1, j, :] / cc[0, j, :])
ax4.plot(p.ste.t_evo, ss[-1, j, :] / ss[0, j, :])
p_final = []
p_final1 = []
for k, t_evo_k in enumerate(p.ste.t_evo):
res = curve_fit(ste, p.ste.t_mix, cc[:, j, k], p0=p0)
res2 = curve_fit(ste, p.ste.t_mix, ss[:, j, k], p0=p0)
p_final.append(res[0].tolist())
p_final1.append(res2[0].tolist())
p_final = np.array(p_final)
p_final1 = np.array(p_final1)
ax.plot(p.ste.t_evo, p_final[:, 0])
ax.plot(p.ste.t_evo, p_final1[:, 0])
ax.plot(p.ste.t_evo, p_final[:, 1])
ax.plot(p.ste.t_evo, p_final1[:, 1])
ax5.semilogy(p.ste.t_evo, p_final[:, 2])
ax5.semilogy(p.ste.t_evo, p_final1[:, 2])
ax2.plot(p.ste.t_evo, p_final[:, 3])
ax2.plot(p.ste.t_evo, p_final1[:, 3])
plt.show()
def print_step(n, num_traj, start):
if (n + 1) % 200 == 0:
elapsed = time() - start
print(f'Step {n + 1} of {num_traj}', end=' - ')
total = num_traj * elapsed / (n + 1)
print(f'total: {total:.2f}s - elapsed: {elapsed:.2f}s - remaining: {total - elapsed:.2f}s')
def make_trajectory(chunks: int, dist, motion, t_max: float):
t_passed = 0
t = [0]
phase = [0]
accumulated_phase = 0
while t_passed < t_max:
# orientation until the next jump
current_omega = motion.jump(size=chunks)
# time to next jump
t_wait = dist.wait(size=chunks)
accumulated_phase = np.cumsum(t_wait * current_omega) + phase[-1]
t_wait = np.cumsum(t_wait) + t_passed
t_passed = t_wait[-1]
t.extend(t_wait.tolist())
phase.extend(accumulated_phase.tolist())
# convenient interpolation to get phase at arbitrary times
phase_interpol = interp1d(t, phase)
return phase_interpol
def _prepare_sim(parameter: Parameter) -> tuple[Generator, int, float, float, float, int]:
# random number generator
rng = np.random.default_rng(parameter.sim.seed)
# number of random walkers
num_traj = parameter.sim.num_walker
# length of trajectories
t_max = parameter.sim.t_max
# parameter for omega_q
delta, eta = parameter.molecule.delta, parameter.molecule.eta
num_variables = parameter.dist.num_variables + parameter.motion.num_variables
return rng, num_traj, t_max, delta, eta, num_variables
if __name__ == '__main__':
run_ste_sim('../config.json')
run_spectrum_sim('../config.json')