def one_step_for_sqrtBetas(self, Layers):
sqrt_beta_noises = self.stdev_sqrtBetas * np.random.randn(
self.n_layers)
propSqrtBetas = np.zeros(self.n_layers, dtype=np.float64)
for i in range(self.n_layers):
temp = np.sqrt(1 - self.pcn_step_sqrtBetas**2) * Layers[
i].sqrt_beta + self.pcn_step_sqrtBetas * sqrt_beta_noises[i]
propSqrtBetas[i] = max(temp, 1e-4)
if i == 0:
stdev_sym_temp = (propSqrtBetas[i] /
Layers[i].sqrt_beta) * Layers[i].stdev_sym
Layers[i].new_sample_sym = stdev_sym_temp * Layers[
i].current_noise_sample
else:
Layers[i].LMat.construct_from_with_sqrt_beta(
Layers[i - 1].new_sample, propSqrtBetas[i])
if i < self.n_layers - 1:
Layers[i].new_sample_sym = np.linalg.solve(
Layers[i].LMat.latest_computed_L,
Layers[i].current_noise_sample)
else:
wNew = Layers[-1].current_noise_sample
eNew = np.random.randn(self.measurement.num_sample)
wBar = np.concatenate((eNew, wNew))
LBar = np.vstack(
(self.H, Layers[-1].LMat.latest_computed_L))
v, res, rnk, s = np.linalg.lstsq(LBar, self.yBar - wBar)
Layers[-1].new_sample_sym = v
Layers[i].new_sample = Layers[i].new_sample_sym[
self.fourier.basis_number_2D_ravel - 1:]
logRatio = 0.5 * (util.norm2(self.y / self.measurement.stdev -
self.H @ Layers[-1].current_sample_sym))
logRatio -= 0.5 * (util.norm2(self.y / self.measurement.stdev -
self.H @ Layers[-1].new_sample_sym))
if logRatio > np.log(np.random.rand()):
# print('Proposal sqrt_beta accepted!')
self.Layers_sqrtBetas = propSqrtBetas
for i in range(self.n_layers):
Layers[i].sqrt_beta = propSqrtBetas[i]
Layers[i].LMat.set_current_L_to_latest()
if Layers[i].is_stationary:
Layers[i].stdev_sym = stdev_sym_temp
Layers[i].stdev = Layers[i].stdev_sym[
self.fourier.basis_number_2D_ravel - 1:]
def one_step_non_centered_sari(self,Layers):
accepted = 0
Layers[self.n_layers-1].sample_non_centered()
wNew = Layers[self.n_layers-1].new_noise_sample
eNew = np.random.randn(self.measurement.num_sample)
wBar = np.concatenate((eNew,wNew))
LBar = np.vstack((self.H,Layers[self.n_layers-1].LMat.current_L))
v, res, rnk, s = np.linalg.lstsq(LBar,self.yBar-wBar )#,rcond=None)
Layers[self.n_layers-1].new_sample_sym = v
Layers[self.n_layers-1].new_sample = v[self.fourier.basis_number-1:]
logRatio = 0.0
for i in range(self.n_layers):
if i<self.n_layers-1:
Layers[i].sample_non_centered()
if i>0:
Layers[i].LMat.construct_from(Layers[i-1].new_sample)
if i<self.n_layers-1:
Layers[i].new_sample_sym = np.linalg.solve(Layers[i].LMat.latest_computed_L,Layers[i].new_noise_sample)
else:
Layers[i].new_sample_sym = Layers[i].stdev_sym*Layers[i].new_noise_sample
Layers[i].new_sample = Layers[i].new_sample_sym[self.fourier.basis_number-1:]
if i == self.n_layers-1:
logRatio += Layers[i].LMat.logDet(True) - Layers[i].LMat.logDet(False)
logRatio += 0.5*(util.norm2(Layers[i].LMat.current_L@v)-util.norm2(Layers[i].LMat.latest_computed_L@v))
if i<self.n_layers-1:
logRatio += 0.5*(util.norm2(Layers[i].current_noise_sample) - util.norm2(Layers[i].new_noise_sample))
if logRatio>np.log(np.random.rand()):
accepted = 1
for i in range(self.n_layers):
Layers[i].update_current_sample()
if i<self.n_layers-1 and not Layers[i+1].is_stationary:
Layers[i+1].LMat.set_current_L_to_latest()
# only record when needed
if (self.record_count%self.record_skip) == 0:
# print('recorded')
for i in range(self.n_layers):
Layers[i].record_sample()
self.record_count += 1
return accepted
def __init__(self, is_stationary, sqrt_beta, order_number, n_samples, pcn,
init_sample):
self.is_stationary = is_stationary
self.sqrt_beta = sqrt_beta
self.order_number = order_number
self.n_samples = n_samples
self.pcn = pcn
zero_compl_dummy = np.zeros(self.pcn.fourier.basis_number_2D_ravel,
dtype=np.complex128)
ones_compl_dummy = np.ones(self.pcn.fourier.basis_number_2D_ravel,
dtype=np.complex128)
self.stdev = ones_compl_dummy
self.stdev_sym = util.symmetrize(self.stdev)
self.samples_history = np.empty(
(self.n_samples, self.pcn.fourier.basis_number_2D_ravel),
dtype=np.complex128)
self.LMat = Lmatrix_2D(self.pcn.fourier, self.sqrt_beta)
self.current_noise_sample = self.pcn.random_gen.construct_w(
) #noise sample always symmetric
self.new_noise_sample = self.current_noise_sample.copy()
if self.is_stationary:
self.current_sample = init_sample
self.new_sample = init_sample
self.new_sample_sym = self.pcn.random_gen.symmetrize(
self.new_sample)
self.new_sample_scaled_norm = 0
self.new_log_L_det = 0
#numba need this initialization. otherwise it will not compile
self.current_sample = init_sample.copy()
self.current_sample_scaled_norm = 0
self.current_log_L_det = 0
else:
self.LMat.construct_from(init_sample)
self.LMat.set_current_L_to_latest()
self.new_sample_sym = np.linalg.solve(
self.LMat.current_L, self.pcn.random_gen.construct_w())
self.new_sample = self.new_sample_sym[self.pcn.fourier.
basis_number_2D_ravel - 1:]
self.new_sample_scaled_norm = util.norm2(
self.LMat.current_L @ self.new_sample_sym) #ToDO: Modify this
self.new_log_L_det = self.LMat.logDet(True) #ToDO: Modify this
# #numba need this initialization. otherwise it will not compile
self.current_sample = init_sample.copy()
self.current_sample_sym = self.new_sample_sym.copy()
self.current_sample_scaled_norm = self.new_sample_scaled_norm
self.current_log_L_det = self.new_log_L_det
# self.update_current_sample()
self.i_record = 0
def oneStep(self,Layers):
logRatio = 0.0
for i in range(self.n_layers):
# i = int(self.gibbs_step//len(Layers))
Layers[i].sample()
# new_sample = Layers[i].new_sample
if i> 0:
Layers[i].LMat.construct_from(Layers[i-1].new_sample)
Layers[i].new_log_L_det = np.linalg.slogdet(Layers[i].LMat.latest_computed_L)[1]
# if i < self.n_layers - 1 :
# Layers[i].current_sample_scaled_norm = util.norm2(Layers[i].LMat.current_L@Layers[i].current_sample_sym)
# else:
Layers[i].current_sample_scaled_norm = util.norm2(Layers[i].LMat.current_L@Layers[i].new_sample_sym)
Layers[i].new_sample_scaled_norm = util.norm2(Layers[i].LMat.latest_computed_L@Layers[i].new_sample_sym)
logRatio += 0.5*(Layers[i].current_sample_scaled_norm-Layers[i].new_sample_scaled_norm)
logRatio += (Layers[i].new_log_L_det-Layers[i].current_log_L_det)
else:
#TODO: Check whether 0.5 factor should be added below
Layers[i].new_sample_scaled_norm = util.norm2(Layers[i].new_sample/Layers[i].stdev)
logRatio += (Layers[i].current_sample_scaled_norm-Layers[i].new_sample_scaled_norm)
if logRatio>np.log(np.random.rand()):
for i in range(self.n_layers):
Layers[i].update_current_sample()
if not Layers[i].is_stationary:
Layers[i].LMat.set_current_L_to_latest()
accepted = 1
else:
accepted=0
# self.gibbs_step +=1
# only record when needed
if (self.record_count%self.record_skip) == 0:
# print('recorded')
for i in range(self.n_layers):
Layers[i].record_sample()
self.record_count += 1
return accepted
def oneStep(self, v):
norm_L_v_2 = util.norm2(self.LMat.current_L @ v)
newSample = self.sample()
newL = self.LMat.construct_from(newSample)
log_det_newL = (np.linalg.slogdet(newL)[1])
norm_newL_v_2 = util.norm2(newL @ v)
norm_new_sample = util.norm2(newSample / self.uStdev)
logRatio = self.computelogRatio(norm_L_v_2, norm_newL_v_2,
norm_new_sample, log_det_newL)
if logRatio > np.log(np.random.rand()):
self.current_sample = newSample
self.norm_current_sample = norm_new_sample
self.current_log_det_L = log_det_newL
self.LMat.set_current_L_to_latest()
accepted = 1
else:
accepted = 0
return accepted
def __init__(self, LMat, rg, uStdev, init_sample, beta=1):
self.LMat = LMat
self.rand_gen = rg
self.uStdev = uStdev
self.beta = beta
self.betaZ = 1 - np.sqrt(beta**2)
#TODO: modify this
self.current_sample = init_sample
self.LMat.construct_from(init_sample)
self.LMat.set_current_L_to_latest()
self.norm_current_sample = util.norm2(self.current_sample /
self.uStdev)
self.current_log_det_L = self.LMat.logDet()
def negLogPosterior(x,Layers):
"""
Layers are numba typed List
"""
negLogPost = 0.0
uHalf_all = xToUHalf(x) # this is just like having new sample at the bottom layer
n = Layers[0].pcn.fourier.fourier_basis_number
uHalf_0 = uHalf_all[0:n]
Layers[0].new_sample = uHalf_0
Layers[0].new_sample_sym = Layers[0].pcn.random_gen.symmetrize(Layers[0].new_sample)
Layers[0].new_sample_scaled_norm = util.norm2(Layers[0].new_sample/Layers[0].stdev)
Layers[0].update_current_sample()
negLogPost += Layers[0].current_sample_scaled_norm
for i in range(1,len(Layers)):
Layers[i].LMat.construct_from(Layers[i-1].new_sample)
Layers[i].new_log_L_det = np.linalg.slogdet(Layers[i].LMat.latest_computed_L)[1]
Layers[i].LMat.set_current_L_to_latest()
# Layers[i].sample()
if i== len(Layers)-1:
wNew = util.symmetrize(uHalf_all[n*(i-1):n*i])
eNew = np.random.randn(Layers[i].pcn.measurement.num_sample)
wBar = np.concatenate((eNew,wNew))
LBar = np.vstack((Layers[i].pcn.H,Layers[i].LMat.current_L))
Layers[i].new_sample_sym, res, rnk, s = np.linalg.lstsq(LBar,Layers[i].pcn.yBar-wBar )#,rcond=None)
Layers[i].new_sample = Layers[i].new_sample_sym[Layers[i].pcn.fourier.fourier_basis_number-1:]
else:
uHalf_i = uHalf_all[n*(i-1):n*i]
Layers[i].new_sample = uHalf_i
Layers[i].current_sample_scaled_norm = util.norm2(Layers[i].LMat.current_L@Layers[i].new_sample_sym)
Layers[i].update_current_sample()
negLogPost += 0.5*Layers[i].current_sample_scaled_norm
negLogPost -= Layers[i].current_log_L_det
# self.current_neg_log_posterior = negLogPost
return negLogPost
def __init__(self, is_stationary, sqrt_beta, order_number, n_samples, pcn,
init_sample):
self.is_stationary = is_stationary
self.sqrt_beta = sqrt_beta
self.order_number = order_number
# self.current_above_sample = above_sample
self.n_samples = n_samples
#dummy declaration
# a_pcn = pCN.pCN(pcn.n_layers,pcn.random_gen,pcn.measurement,pcn.fourier,pcn.beta)#numba cannot understand without this
# self.pcn = a_pcn
self.pcn = pcn
# self.current_sample = np.zeros(f.basis_number,dtype=np.complex128)
zero_compl_dummy = np.zeros(self.pcn.fourier.basis_number,
dtype=np.complex128)
ones_compl_dummy = np.ones(self.pcn.fourier.basis_number,
dtype=np.complex128)
self.stdev = ones_compl_dummy
self.stdev_sym = util.symmetrize(self.stdev)
self.samples_history = np.empty(
(self.n_samples, self.pcn.fourier.basis_number),
dtype=np.complex128)
#dummy declaration
fpcn = self.pcn.fourier
f = fourier.FourierAnalysis(
fpcn.basis_number, fpcn.extended_basis_number, fpcn.t_start,
fpcn.t_end) #numba cannot understand without this
LMat = L.Lmatrix(f, self.sqrt_beta)
# LMat.fourier = self.pcn.fourier
self.LMat = LMat
self.current_noise_sample = self.pcn.random_gen.construct_w(
) #noise sample always symmetric
self.new_noise_sample = self.current_noise_sample.copy()
if self.is_stationary:
self.current_sample = init_sample
self.new_sample = init_sample
self.new_sample_sym = self.pcn.random_gen.symmetrize(
self.new_sample)
self.new_sample_scaled_norm = 0
self.new_log_L_det = 0
#numba need this initialization. otherwise it will not compile
self.current_sample = init_sample.copy()
self.current_sample_sym = self.new_sample_sym.copy()
self.current_sample_scaled_norm = 0
self.current_log_L_det = 0
else:
zero_init = np.zeros(self.pcn.fourier.basis_number,
dtype=np.complex128)
self.LMat.construct_from(init_sample)
self.LMat.set_current_L_to_latest()
self.new_sample_sym = np.linalg.solve(
self.LMat.current_L, self.pcn.random_gen.construct_w())
self.new_sample = self.new_sample_sym[self.pcn.fourier.
basis_number - 1:]
self.new_sample_scaled_norm = util.norm2(
self.LMat.current_L @ self.new_sample_sym) #ToDO: Modify this
self.new_log_L_det = self.LMat.logDet(True) #ToDO: Modify this
# #numba need this initialization. otherwise it will not compile
self.current_sample = init_sample.copy()
self.current_sample_sym = self.new_sample_sym.copy()
self.current_sample_scaled_norm = self.new_sample_scaled_norm
self.current_log_L_det = self.new_log_L_det
# self.update_current_sample()
self.i_record = 0
# n_layers = 2
# Layers = List()
typed_list_status = importlib.util.find_spec('numba.typed.typedlist')
if typed_list_status is None:
Layers = []
else:
from numba.typed.typedlist import List
Layers = List()
# factor = 1e-8
for i in range(n_layers):
if i == 0:
init_sample = np.linalg.solve(
Lu, random_gen.construct_w())[f.fourier_basis_number - 1:]
lay = layer.Layer(True, sqrtBeta_0, i, n_samples, pcn, init_sample)
lay.stdev = uStdev
lay.current_sample_scaled_norm = util.norm2(
lay.current_sample / lay.stdev) #ToDO: Modify this
lay.new_sample_scaled_norm = lay.current_sample_scaled_norm
else:
if i == n_layers - 1:
lay = layer.Layer(False, sqrtBeta_v, i, n_samples, pcn,
Layers[i - 1].current_sample)
wNew = pcn.random_gen.construct_w()
eNew = np.random.randn(pcn.measurement.num_sample)
wBar = np.concatenate((eNew, wNew))
LBar = np.vstack((pcn.H, lay.LMat.current_L))
#update v
lay.current_sample_symmetrized, res, rnk, s = np.linalg.lstsq(
def __init__(self, n_layers, n_samples, n, beta, num, kappa, sigma_0,
sigma_v, sigma_scaling, evaluation_interval, printProgress,
seed, burn_percentage, enable_beta_feedback, pcn_variant,
measurement_signal_type):
self.n_samples = n_samples
self.meas_samples_num = num
self.evaluation_interval = evaluation_interval
self.burn_percentage = burn_percentage
#set random seed
self.random_seed = seed
self.printProgress = printProgress
self.n_layers = n_layers
self.kappa = kappa
self.sigma_0 = sigma_0
self.sigma_v = sigma_v
self.sigma_scaling = sigma_scaling
self.enable_beta_feedback = enable_beta_feedback
np.random.seed(self.random_seed)
#setup parameters for 1 Dimensional simulation
self.d = 1
self.nu = 2 - self.d / 2
self.alpha = self.nu + self.d / 2
self.t_start = 0.0
self.t_end = 1.0
self.beta_0 = (sigma_0**2) * (
2**self.d * np.pi**(self.d / 2)
) * 1.1283791670955126 #<-- this numerical value is scp.special.gamma(alpha))/scp.special.gamma(nu)
self.beta_v = self.beta_0 * (sigma_v / sigma_0)**2
self.sqrtBeta_v = np.sqrt(self.beta_v)
self.sqrtBeta_0 = np.sqrt(self.beta_0)
f = fourier.FourierAnalysis(n, num, self.t_start, self.t_end)
self.fourier = f
rg = randomGenerator.RandomGenerator(f.basis_number)
self.random_gen = rg
LuReal = (1 / self.sqrtBeta_0) * (
self.fourier.Dmatrix * self.kappa**(-self.nu) -
self.kappa**(2 - self.nu) * self.fourier.Imatrix)
Lu = LuReal + 1j * np.zeros(LuReal.shape)
uStdev = -1 / np.diag(Lu)
# uStdev = uStdev[self.fourier.basis_number-1:]
# uStdev[0] /= 2 #scaled
meas_std = 0.1
measurement = meas.Measurement(num, meas_std, self.t_start, self.t_end,
measurement_signal_type)
# pcn = pCN.pCN(n_layers,rg,measurement,f,beta)
self.pcn_variant = pcn_variant
self.pcn = pCN.pCN(n_layers, rg, measurement, f, beta,
self.pcn_variant)
# self.pcn_pair_layers = pcn_pair_layers
#initialize Layers
typed_list_status = importlib.util.find_spec('numba.typed.typedlist')
if typed_list_status is None:
Layers = []
else:
from numba.typed.typedlist import List
Layers = List()
# Layers = []
# factor = 1e-8
self.pcn.record_skip = np.max(
[1, self.n_samples // self.pcn.max_record_history])
history_length = np.min([self.n_samples, self.pcn.max_record_history])
self.pcn.sqrtBetas_history = np.empty((history_length, self.n_layers),
dtype=np.float64)
for i in range(self.n_layers):
if i == 0:
init_sample = np.linalg.solve(
Lu,
self.random_gen.construct_w())[self.fourier.basis_number -
1:]
lay = layer.Layer(True, self.sqrtBeta_0, i, self.n_samples,
self.pcn, init_sample)
lay.LMat.current_L = Lu
lay.LMat.latest_computed_L = Lu
lay.stdev_sym = uStdev
lay.stdev = uStdev[self.fourier.basis_number - 1:]
lay.stdev[0] /= 2
lay.current_sample_scaled_norm = util.norm2(
lay.current_sample / lay.stdev) #ToDO: Modify this
lay.new_sample_scaled_norm = lay.current_sample_scaled_norm
else:
if i == n_layers - 1:
lay = layer.Layer(False, self.sqrtBeta_v, i,
self.n_samples, self.pcn,
Layers[i - 1].current_sample)
wNew = self.pcn.random_gen.construct_w()
eNew = np.random.randn(self.pcn.measurement.num_sample)
wBar = np.concatenate((eNew, wNew))
LBar = np.vstack((self.pcn.H, lay.LMat.current_L))
#update v
lay.current_sample_sym, res, rnk, s = np.linalg.lstsq(
LBar, self.pcn.yBar - wBar, rcond=-1) #,rcond=None)
lay.current_sample = lay.current_sample_sym[
self.pcn.fourier.basis_number - 1:]
else:
# lay = layer.Layer(False,self.sqrtBeta_v*np.sqrt(sigma_scaling),i,self.n_samples,self.pcn,Layers[i-1].current_sample)
lay = layer.Layer(False, self.sqrtBeta_v * sigma_scaling,
i, self.n_samples, self.pcn,
Layers[i - 1].current_sample)
lay.update_current_sample()
self.pcn.Layers_sqrtBetas[i] = lay.sqrt_beta
# if self.pcn_variant:
# self.pcn.record_skip = np.max([1,(lay.n_samples*self.n_layers)//self.pcn.max_record_history])
# history_length = np.min([lay.n_samples*(self.n_layers),self.pcn.max_record_history])
# else:
lay.samples_history = np.empty(
(history_length, self.fourier.basis_number),
dtype=np.complex128)
Layers.append(lay)
self.Layers = Layers
sim_result = simRes.SimulationResult()
self.sim_result = sim_result
def one_step_for_sqrtBetas(self,Layers):
accepted_SqrtBeta = 0
sqrt_beta_noises = self.stdev_sqrtBetas*np.random.randn(self.n_layers)
# sqrtBetas = np.zeros(self.n_layers,dtype=np.float64)
propSqrtBetas = np.zeros(self.n_layers,dtype=np.float64)
for i in range(self.n_layers):
# temp = np.sqrt(1-self.pcn_step_sqrtBetas**2)*Layers[i].sqrt_beta + self.pcn_step_sqrtBetas*sqrt_beta_noises[i]
temp = self.pcn_step_sqrtBetas_Z*np.log(Layers[i].sqrt_beta) + self.pcn_step_sqrtBetas*sqrt_beta_noises[i]
propSqrtBetas[i] = np.exp(temp)
if i==0:
stdev_sym_temp = (propSqrtBetas[i]/Layers[i].sqrt_beta)*Layers[i].stdev_sym
Layers[i].new_sample_sym = stdev_sym_temp*Layers[i].current_noise_sample
else:
Layers[i].LMat.construct_from_with_sqrt_beta(Layers[i-1].new_sample,propSqrtBetas[i])
if i < self.n_layers-1:
Layers[i].new_sample_sym = np.linalg.solve(Layers[i].LMat.latest_computed_L,Layers[i].current_noise_sample)
else:
wNew = Layers[-1].current_noise_sample
eNew = np.random.randn(self.measurement.num_sample)
wBar = np.concatenate((eNew,wNew))
LBar = np.vstack((self.H,Layers[-1].LMat.latest_computed_L))
v, res, rnk, s = np.linalg.lstsq(LBar,self.yBar-wBar )
Layers[-1].new_sample_sym = v
Layers[i].new_sample = Layers[i].new_sample_sym[self.fourier.basis_number-1:]
logRatio = 0.5*(util.norm2(self.y/self.measurement.stdev - self.H@Layers[-1].current_sample_sym))
logRatio -= 0.5*(util.norm2(self.y/self.measurement.stdev - self.H@Layers[-1].new_sample_sym))
if logRatio>np.log(np.random.rand()):
acceptedBeta = 1
# print('Proposal sqrt_beta accepted!')
self.Layers_sqrtBetas = propSqrtBetas
for i in range(self.n_layers):
Layers[i].sqrt_beta = propSqrtBetas[i]
Layers[i].LMat.set_current_L_to_latest()
if Layers[i].is_stationary:
Layers[i].stdev_sym = stdev_sym_temp
Layers[i].stdev = Layers[i].stdev_sym[self.fourier.basis_number-1:]
return accepted_SqrtBeta
# def one_step_non_centered_new(self,Layers):
# accepted = 0
# for i in range(self.n_layers):
# Layers[i].sample_non_centered()
# if i>0:
# Layers[i].LMat.construct_from(Layers[i-1].new_sample)
# # if i<self.n_layers-1:
# Layers[i].new_sample_sym = np.linalg.solve(Layers[i].LMat.latest_computed_L,Layers[i].new_noise_sample)
# else:
# Layers[i].new_sample_sym = Layers[i].stdev_sym*Layers[i].new_noise_sample
# Layers[i].new_sample = Layers[i].new_sample_sym[self.fourier.basis_number-1:]
# logRatio = 0.5*(util.norm2(self.measurement.yt/self.measurement.stdev - self.H@Layers[self.n_layers-1].current_sample_sym) - util.norm2(self.measurement.yt/self.measurement.stdev - self.H@Layers[self.n_layers-1].new_sample_sym))
# # a = np.min(np.array([1,np.exp(logRatio)]))
# if logRatio>np.log(np.random.rand()):
# # if a>np.random.rand():
# accepted = 1
# for i in range(self.n_layers):
# Layers[i].update_current_sample()
# if not Layers[i].is_stationary:
# Layers[i].LMat.set_current_L_to_latest()
# # only record when needed
# if (self.record_count%self.record_skip) == 0:
# # print('recorded')
# for i in range(self.n_layers):
# Layers[i].record_sample()
# self.record_count += 1
# return accepted
# def one_step_one_element(self,Layers,element_index):
# logRatio = 0.0
# for i in range(self.n_layers):
# # i = int(self.gibbs_step//len(Layers))
# if i == 0:
# Layers[i].sample_one_element(element_index)
# else:
# Layers[i].sample()
# # new_sample = Layers[i].new_sample
# if i> 0:
# Layers[i].LMat.construct_from(Layers[i-1].new_sample)
# Layers[i].new_log_L_det = (np.linalg.slogdet(Layers[i].LMat.latest_computed_L)[1])
# Layers[i].current_sample_scaled_norm = util.norm2(Layers[i].LMat.current_L@Layers[i].new_sample_sym)
# Layers[i].new_sample_scaled_norm = util.norm2(Layers[i].LMat.latest_computed_L@Layers[i].new_sample_sym)
# logRatio += 0.5*(Layers[i].current_sample_scaled_norm-Layers[i].new_sample_scaled_norm)
# logRatio += (Layers[i].new_log_L_det-Layers[i].current_log_L_det)
# else:
# #TODO: Check whether 0.5 factor should be added below
# # Layers[i].new_sample_scaled_norm = util.norm2(Layers[i].new_sample/Layers[i].stdev)
# # logRatio += (Layers[i].current_sample_scaled_norm-Layers[i].new_sample_scaled_norm)
# logRatio += np.abs((Layers[i].new_sample[element_index]-Layers[i].current_sample[element_index])/Layers[i].stdev[element_index].real)**2
# if logRatio>np.log(np.random.rand()):
# for i in range(self.n_layers):
# Layers[i].update_current_sample()
# if not Layers[i].is_stationary:
# Layers[i].LMat.set_current_L_to_latest()
# accepted = 1
# else:
# accepted=0
# # self.gibbs_step +=1
# for i in range(self.n_layers):
# Layers[i].record_sample()
# return accepted
# def oneStep_pair(self,Layers):
# accepted = 0
# for i in range(self.n_layers-1,0,-1):#do it from the back
# # i = int(self.gibbs_step//len(Layers))
# logRatio = 0.0
# if i == self.n_layers-1:
# Layers[i].sample()
# Layers[i-1].sample()
# #Layer i
# Layers[i].LMat.construct_from(Layers[i-1].new_sample)
# Layers[i].new_log_L_det = np.linalg.slogdet(Layers[i].LMat.latest_computed_L)[1]
# Layers[i].current_sample_scaled_norm = util.norm2(Layers[i].LMat.current_L@Layers[i].new_sample_sym)
# # assert Layers[i].current_sample_scaled_norm != np.nan
# Layers[i].new_sample_scaled_norm = util.norm2(Layers[i].LMat.latest_computed_L@Layers[i].new_sample_sym)
# # assert Layers[i].new_sample_scaled_norm != np.nan
# logRatio += 0.5*(Layers[i].current_sample_scaled_norm-Layers[i].new_sample_scaled_norm)
# logRatio += (Layers[i].new_log_L_det-Layers[i].current_log_L_det)
# #Layer i-1
# if i-1>0:
# Layers[i-1].new_sample_scaled_norm = util.norm2(Layers[i-1].LMat.current_L@Layers[i-1].new_sample_sym)
# else:
# Layers[i-1].new_sample_scaled_norm = util.norm2(Layers[i-1].new_sample/Layers[i-1].stdev)
# logRatio += 0.5*(Layers[i-1].current_sample_scaled_norm-Layers[i-1].new_sample_scaled_norm)
# if logRatio>np.log(np.random.rand()):
# for i in range(self.n_layers):
# Layers[i].update_current_sample()
# if not Layers[i].is_stationary:
# Layers[i].LMat.set_current_L_to_latest()
# accepted += 1
# # for i in range(self.n_layers):
# # Layers[i].record_sample()
# # only record when needed
# if (self.record_count%self.record_skip) == 0:
# # print('recorded')
# for i in range(self.n_layers):
# Layers[i].record_sample()
# self.record_count += 1
# return accepted