python/rwsims/sims.py
2024-08-03 19:04:13 +02:00

218 lines
6.9 KiB
Python

from __future__ import annotations
from time import perf_counter
import numpy as np
from numpy.random import Generator
from datetime import datetime
from scipy.interpolate import interp1d
import matplotlib.pyplot as plt
from .spectrum import save_spectrum_data
from .ste import save_ste_data, fit_ste, save_ste_fit, plot_ste_fits
from .parameter import Parameter
from .distributions import BaseDistribution
from .motions import BaseMotion
from .parsing import parse
def run_ste_sim(config_file: str):
p = parse(config_file)
rng, num_traj, t_max, delta, eta, num_variables = _prepare_sim(p)
t_mix = p.ste.t_mix
t_evo = p.ste.t_evo
t_echo = p.ste.t_echo
fits_cc = []
fits_ss = []
# 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)
# second loop over parameter of motion model
for (j, motion_values) in enumerate(p.motion):
# noinspection PyCallingNonCallable
motion = p.motion.model(delta, eta, **motion_values, rng=rng)
print(f'\nStart of {dist}, {motion}')
start = last_print = perf_counter()
cc = np.zeros((len(t_mix), len(t_evo)))
ss = np.zeros((len(t_mix), len(t_evo)))
# inner loop to create trajectories
for n in range(num_traj):
phase = make_trajectory(dist, motion, t_max)
for (k, t_evo_k) in enumerate(t_evo):
dephased = phase(t_evo_k)
t0 = t_mix + t_evo_k
rephased = phase(t0 + t_evo_k + 2*t_echo) + phase(t0) - 2 * phase(t0+t_echo)
cc[:, k] += np.cos(dephased)*np.cos(rephased)
ss[:, k] += np.sin(dephased)*np.sin(rephased)
last_print = print_step(n, num_traj, start, last_print)
cc[:, 1:] /= num_traj
ss[:, 1:] /= num_traj
save_ste_data(cc, ss, p, dist, motion)
p_fit_cc, p_fit_ss = fit_ste(cc, ss, t_evo, t_mix, dist_values, num_variables)
fits_cc.append(p_fit_cc)
fits_ss.append(p_fit_ss)
save_ste_fit(p_fit_cc, p_fit_ss, p, dist, motion)
plot_ste_fits(fits_cc, fits_ss, p.dist, p.motion)
plt.show()
def run_spectrum_sim(config_file: str):
p: Parameter = 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))
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)
# second loop over parameter of motion model
for (j, motion_values) in enumerate(p.motion):
# noinspection PyCallingNonCallable
motion = p.motion.model(delta, eta, **motion_values, rng=rng)
print(f'\nStart of {dist}, {motion}')
timesignal = np.zeros((p.spec.num_points, num_echos))
start = perf_counter()
last_print = start
# inner loop to create trajectories
for n in range(num_traj):
phase = make_trajectory(dist, motion, t_max)
for (k, t_echo_k) in enumerate(t_echo):
# effect of de-phasing and re-phasing
start_amp = -2 * phase(t_echo_k)
# start of actual acquisition
timesignal[:, k] += np.cos(start_amp + phase(p.spec.t_acq + 2*t_echo_k))
reduction_factor[max(p.motion.num_variables, 1)*i+j, k] += np.cos(phase(2*t_echo_k) + start_amp)
# print(n+1, num_traj, start, last_print)
last_print = print_step(n+1, num_traj, start, last_print)
# apply line broadening
timesignal *= p.spec.dampening[:, None]
timesignal /= num_traj
timesignal[0, :] /= 2
# FT to spectrum
spec = np.fft.fftshift(np.fft.fft(timesignal, axis=0), axes=0).real
spec -= spec[0]
spec *= p.spec.pulse_attn[:, None]
# save timesignals and spectra, also plots them
save_spectrum_data(timesignal, spec, p, dist, motion, t_echo_strings)
# plot and save reduction factor
reduction_factor /= num_traj
fig, ax = plt.subplots()
lines = ax.semilogx(p.dist.variables['tau'], reduction_factor, 'o--')
ax.legend(lines, t_echo_strings)
plt.savefig(f'{dist.name()}_{motion.name()}_reduction.png')
plt.show()
def make_trajectory(
dist: BaseDistribution,
motion: BaseMotion,
t_max: float,
t_passed: float = 0.,
init_phase: float = 0.
):
# set initial orientations and correlation times
motion.start()
dist.start()
# number of jumps that are simulated at once
chunks = min(int(0.51 * t_max / dist.tau_jump), 100_000) + 1
t = [np.array([t_passed])]
phase = [np.array([init_phase])]
while t_passed < t_max:
# frequencies between jumps
current_omega = motion.jump(size=chunks)
# times at a particular position
t_wait = dist.wait(size=chunks)
accumulated_phase = np.cumsum(t_wait * current_omega) + phase[-1][-1]
phase.append(accumulated_phase)
t_wait = np.cumsum(t_wait) + t_passed
t_passed = t_wait[-1]
t.append(t_wait)
t = np.concatenate(t)
phase = np.concatenate(phase)
# 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]:
# collect variables that are common to spectra and stimulated echo
# 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
def print_step(n: int, num_traj: int, start: float, last_print: float) -> float:
step_time = perf_counter()
dt = step_time - last_print
if dt > 10 or n == num_traj:
date = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
print(f'{date} - step {n} of {num_traj}', end=' - ')
elapsed = step_time - start
total = num_traj * elapsed / n
print(f'expected total: {total:.2f}s - elapsed: {elapsed:.2f}s - remaining: {total - elapsed:.2f}s')
if dt > 10:
last_print = step_time
return last_print