Add more about evidence and selection to flow (#142)

* Add Laplace evidence

* Numerically stable laplace evidence

* Minor edits to Laplace

* Remove rmax

* Rm old things

* Rm comments

* Add script

* Add super toy selection

* Add super toy selection

* Update script
This commit is contained in:
Richard Stiskalek 2024-08-27 00:36:00 +02:00 committed by GitHub
parent d13246a394
commit 3d1e1c0ae3
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8 changed files with 243 additions and 57 deletions

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@ -17,3 +17,4 @@ from .flow_model import (DataLoader, PV_LogLikelihood, PV_validation_model,
Observed2CosmologicalRedshift, predict_zobs, # noqa
project_Vext, radial_velocity_los, # noqa
stack_pzosmo_over_realizations) # noqa
from .selection import ToyMagnitudeSelection # noqa

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@ -35,6 +35,7 @@ from numpyro.distributions import Normal, Uniform, MultivariateNormal
from quadax import simpson
from tqdm import trange
from .selection import toy_log_magnitude_selection
from ..params import SPEED_OF_LIGHT, simname2Omega_m
from ..utils import fprint, radec_to_galactic, radec_to_supergalactic
@ -78,7 +79,7 @@ class DataLoader:
self._catname = catalogue
fprint("reading the interpolated field.", verbose)
self._field_rdist, self._los_density, self._los_velocity, self._rmax = self._read_field( # noqa
self._field_rdist, self._los_density, self._los_velocity = self._read_field( # noqa
simname, ksim, catalogue, ksmooth, paths)
if len(self._cat) != self._los_density.shape[1]:
@ -169,14 +170,6 @@ class DataLoader:
return self._los_velocity[:, :, self._mask, ...]
@property
def rmax(self):
"""
Radial distance above which the underlying reconstruction is
extrapolated `(n_sims, n_objects)`.
"""
return self._rmax[:, self._mask]
@property
def los_radial_velocity(self):
"""
@ -201,7 +194,6 @@ class DataLoader:
los_density = [None] * len(ksims)
los_velocity = [None] * len(ksims)
rmax = [None] * len(ksims)
for n, ksim in enumerate(ksims):
nsim = nsims[ksim]
@ -216,13 +208,11 @@ class DataLoader:
los_density[n] = f[f"density_{nsim}"][indx]
los_velocity[n] = f[f"velocity_{nsim}"][indx]
rdist = f[f"rdist_{nsim}"][...]
rmax[n] = f[f"rmax_{nsim}"][indx]
los_density = np.stack(los_density)
los_velocity = np.stack(los_velocity)
rmax = np.stack(rmax)
return rdist, los_density, los_velocity, rmax
return rdist, los_density, los_velocity
def _read_catalogue(self, catalogue, catalogue_fpath):
if catalogue == "A2":
@ -622,9 +612,6 @@ class PV_LogLikelihood(BaseFlowValidationModel):
LOS density field.
los_velocity : 3-dimensional array of shape (n_sims, n_objects, n_steps)
LOS radial velocity field.
rmax : 1-dimensional array of shape (n_sims, n_objects)
Radial distance above which the underlying reconstruction is
extrapolated.
RA, dec : 1-dimensional arrays of shape (n_objects)
Right ascension and declination in degrees.
z_obs : 1-dimensional array of shape (n_objects)
@ -643,11 +630,13 @@ class PV_LogLikelihood(BaseFlowValidationModel):
Catalogue kind, either "TFR", "SN", or "simple".
name : str
Name of the catalogue.
toy_selection : tuple of length 3, optional
Toy magnitude selection paramers `m1`, `m2` and `a`. Optional.
"""
def __init__(self, los_density, los_velocity, rmax, RA, dec, z_obs,
e_zobs, calibration_params, maxmag_selection, r_xrange,
Omega_m, kind, name):
def __init__(self, los_density, los_velocity, RA, dec, z_obs, e_zobs,
calibration_params, maxmag_selection, r_xrange, Omega_m,
kind, name, toy_selection=None):
if e_zobs is not None:
e2_cz_obs = jnp.asarray((SPEED_OF_LIGHT * e_zobs)**2)
else:
@ -657,9 +646,9 @@ class PV_LogLikelihood(BaseFlowValidationModel):
RA = np.deg2rad(RA)
dec = np.deg2rad(dec)
names = ["los_density", "los_velocity", "rmax", "RA", "dec", "z_obs",
names = ["los_density", "los_velocity", "RA", "dec", "z_obs",
"e2_cz_obs"]
values = [los_density, los_velocity, rmax, RA, dec, z_obs, e2_cz_obs]
values = [los_density, los_velocity, RA, dec, z_obs, e2_cz_obs]
self._setattr_as_jax(names, values)
self._set_calibration_params(calibration_params)
self._set_radial_spacing(r_xrange, Omega_m)
@ -669,6 +658,7 @@ class PV_LogLikelihood(BaseFlowValidationModel):
self.Omega_m = Omega_m
self.norm = - self.ndata * jnp.log(self.num_sims)
self.maxmag_selection = maxmag_selection
self.toy_selection = toy_selection
if kind == "TFR":
self.mag_min, self.mag_max = jnp.min(self.mag), jnp.max(self.mag)
@ -688,6 +678,17 @@ class PV_LogLikelihood(BaseFlowValidationModel):
if maxmag_selection is not None and self.maxmag_selection > self.mag_max: # noqa
raise ValueError("The maximum magnitude cannot be larger than the selection threshold.") # noqa
if toy_selection is not None and self.maxmag_selection is not None:
raise ValueError("`toy_selection` and `maxmag_selection` cannot be used together.") # noqa
if toy_selection is not None:
self.m1, self.m2, self.a = toy_selection
self.log_Fm = toy_log_magnitude_selection(
self.mag, self.m1, self.m2, self.a)
if toy_selection is not None and self.kind != "TFR":
raise ValueError("Toy selection is only implemented for TFRs.")
def __call__(self, field_calibration_params, distmod_params,
inference_method):
if inference_method not in ["mike", "bayes"]:
@ -772,12 +773,30 @@ class PV_LogLikelihood(BaseFlowValidationModel):
mag_true, eta_true = x_true[..., 0], x_true[..., 1]
# Log-likelihood of the observed magnitudes.
if self.maxmag_selection is None:
ll0 += jnp.sum(normal_logpdf(
self.mag, mag_true, self.e_mag))
else:
if self.maxmag_selection is not None:
ll0 += jnp.sum(upper_truncated_normal_logpdf(
self.mag, mag_true, self.e_mag, self.maxmag_selection))
elif self.toy_selection is not None:
ll_mag = self.log_Fm
ll_mag += normal_logpdf(self.mag, mag_true, self.e_mag)
# Normalization per datapoint, initially (ndata, nxrange)
mu_start = mag_true - 5 * self.e_mag
mu_end = mag_true + 5 * self.e_mag
# 100 is a reasonable and sufficient choice.
mu_xrange = jnp.linspace(mu_start, mu_end, 100).T
norm = toy_log_magnitude_selection(
mu_xrange, self.m1, self.m2, self.a)
norm = norm + normal_logpdf(
mu_xrange, mag_true[:, None], self.e_mag[:, None])
# Now integrate over the magnitude range.
norm = simpson(jnp.exp(norm), x=mu_xrange, axis=-1)
ll0 += jnp.sum(ll_mag - jnp.log(norm))
else:
ll0 += jnp.sum(normal_logpdf(
self.mag, mag_true, self.e_mag))
# Log-likelihood of the observed linewidths.
ll0 += jnp.sum(normal_logpdf(eta_true, self.eta, self.e_eta))
@ -876,7 +895,8 @@ def PV_validation_model(models, distmod_hyperparams_per_model,
###############################################################################
def get_model(loader, zcmb_min=0.0, zcmb_max=None, maxmag_selection=None):
def get_model(loader, zcmb_min=0.0, zcmb_max=None, maxmag_selection=None,
toy_selection=None):
"""
Get a model and extract the relevant data from the loader.
@ -890,6 +910,9 @@ def get_model(loader, zcmb_min=0.0, zcmb_max=None, maxmag_selection=None):
Maximum observed redshift in the CMB frame to include.
maxmag_selection : float, optional
Maximum magnitude selection threshold.
toy_selection : tuple of length 3, optional
Toy magnitude selection paramers `m1`, `m2` and `a` for TFRs of the
Boubel+24 model.
Returns
-------
@ -899,7 +922,6 @@ def get_model(loader, zcmb_min=0.0, zcmb_max=None, maxmag_selection=None):
los_overdensity = loader.los_density
los_velocity = loader.los_radial_velocity
rmax = loader.rmax
kind = loader._catname
if maxmag_selection is not None and kind != "2MTF":
@ -917,7 +939,7 @@ def get_model(loader, zcmb_min=0.0, zcmb_max=None, maxmag_selection=None):
"e_c": e_c[mask]}
model = PV_LogLikelihood(
los_overdensity[:, mask], los_velocity[:, mask], rmax[:, mask],
los_overdensity[:, mask], los_velocity[:, mask],
RA[mask], dec[mask], zCMB[mask], e_zCMB, calibration_params,
maxmag_selection, loader.rdist, loader._Omega_m, "SN", name=kind)
elif "Pantheon+" in kind:
@ -945,20 +967,27 @@ def get_model(loader, zcmb_min=0.0, zcmb_max=None, maxmag_selection=None):
"e_mag": e_mB[mask], "e_x1": e_x1[mask],
"e_c": e_c[mask]}
model = PV_LogLikelihood(
los_overdensity[:, mask], los_velocity[:, mask], rmax[:, mask],
los_overdensity[:, mask], los_velocity[:, mask],
RA[mask], dec[mask], zCMB[mask], e_zCMB[mask], calibration_params,
maxmag_selection, loader.rdist, loader._Omega_m, "SN", name=kind)
elif kind in ["SFI_gals", "2MTF", "SFI_gals_masked"]:
keys = ["RA", "DEC", "z_CMB", "mag", "eta", "e_mag", "e_eta"]
RA, dec, zCMB, mag, eta, e_mag, e_eta = (loader.cat[k] for k in keys)
if kind == "SFI_gals" and toy_selection is not None:
if len(toy_selection) != 3:
raise ValueError("Toy selection must be a tuple with 3 elements.") # noqa
m1, m2, a = toy_selection
fprint(f"using toy selection with m1 = {m1}, m2 = {m2}, a = {a}.")
mask = (zCMB < zcmb_max) & (zCMB > zcmb_min)
calibration_params = {"mag": mag[mask], "eta": eta[mask],
"e_mag": e_mag[mask], "e_eta": e_eta[mask]}
model = PV_LogLikelihood(
los_overdensity[:, mask], los_velocity[:, mask], rmax[:, mask],
los_overdensity[:, mask], los_velocity[:, mask],
RA[mask], dec[mask], zCMB[mask], None, calibration_params,
maxmag_selection, loader.rdist, loader._Omega_m, "TFR", name=kind)
maxmag_selection, loader.rdist, loader._Omega_m, "TFR", name=kind,
toy_selection=toy_selection)
elif "CF4_TFR_" in kind:
# The full name can be e.g. "CF4_TFR_not2MTForSFI_i" or "CF4_TFR_i".
band = kind.split("_")[-1]
@ -995,7 +1024,7 @@ def get_model(loader, zcmb_min=0.0, zcmb_max=None, maxmag_selection=None):
calibration_params = {"mag": mag[mask], "eta": eta[mask],
"e_mag": e_mag[mask], "e_eta": e_eta[mask]}
model = PV_LogLikelihood(
los_overdensity[:, mask], los_velocity[:, mask], rmax[:, mask],
los_overdensity[:, mask], los_velocity[:, mask],
RA[mask], dec[mask], z_obs[mask], None, calibration_params,
maxmag_selection, loader.rdist, loader._Omega_m, "TFR", name=kind)
elif kind in ["CF4_GroupAll"]:
@ -1011,7 +1040,7 @@ def get_model(loader, zcmb_min=0.0, zcmb_max=None, maxmag_selection=None):
calibration_params = {"mu": mu[mask], "e_mu": e_mu[mask]}
model = PV_LogLikelihood(
los_overdensity[:, mask], los_velocity[:, mask], rmax[:, mask],
los_overdensity[:, mask], los_velocity[:, mask],
RA[mask], dec[mask], zCMB[mask], None, calibration_params,
maxmag_selection, loader.rdist, loader._Omega_m, "simple",
name=kind)

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@ -0,0 +1,69 @@
# Copyright (C) 2024 Richard Stiskalek
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 3 of the License, or (at your
# option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
# Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
"""Selection functions for peculiar velocities."""
import numpy as np
from jax import numpy as jnp
from scipy.integrate import quad
from scipy.optimize import minimize
class ToyMagnitudeSelection:
"""
Toy magnitude selection according to Boubel et al 2024.
"""
def __init__(self):
pass
def log_true_pdf(self, m, m1):
"""Unnormalized `true' PDF."""
return 0.6 * (m - m1)
def log_selection_function(self, m, m1, m2, a):
return np.where(m <= m1,
0,
a * (m - m2)**2 - a * (m1 - m2)**2 - 0.6 * (m - m1))
def log_observed_pdf(self, m, m1, m2, a):
# Calculate the normalization constant
f = lambda m: 10**(self.log_true_pdf(m, m1) # noqa
+ self.log_selection_function(m, m1, m2, a))
mmin, mmax = 0, 25
norm = quad(f, mmin, mmax)[0]
return (self.log_true_pdf(m, m1)
+ self.log_selection_function(m, m1, m2, a)
- np.log10(norm))
def fit(self, mag):
def loss(x):
m1, m2, a = x
if a >= 0:
return np.inf
return -np.sum(self.log_observed_pdf(mag, m1, m2, a))
x0 = [12.0, 12.5, -0.1]
return minimize(loss, x0, method="Nelder-Mead")
def toy_log_magnitude_selection(mag, m1, m2, a):
"""JAX implementation of `ToyMagnitudeSelection` but natural logarithm."""
return jnp.log(10) * jnp.where(
mag <= m1,
0,
a * (mag - m2)**2 - a * (m1 - m2)**2 - 0.6 * (mag - m1))

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@ -492,6 +492,11 @@ def dict_samples_to_array(samples):
for i in range(value.shape[-1]):
data.append(value[:, i])
names.append(f"{key}_{i}")
elif value.ndim == 3:
for i in range(value.shape[-1]):
for j in range(value.shape[-2]):
data.append(value[:, j, i])
names.append(f"{key}_{j}_{i}")
else:
raise ValueError("Invalid dimensionality of samples to stack.")

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@ -10,7 +10,7 @@ MAS="SPH"
grid=1024
for simname in "Carrick2015"; do
for simname in "Lilow2024"; do
for catalogue in "CF4_TFR"; do
pythoncm="$env $file --catalogue $catalogue --nsims $nsims --simname $simname --MAS $MAS --grid $grid"
if [ $on_login -eq 1 ]; then

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@ -72,7 +72,7 @@ def print_variables(names, variables):
print(flush=True)
def get_models(get_model_kwargs, verbose=True):
def get_models(get_model_kwargs, toy_selection, verbose=True):
"""Load the data and create the NumPyro models."""
paths = csiborgtools.read.Paths(**csiborgtools.paths_glamdring)
folder = "/mnt/extraspace/rstiskalek/catalogs/"
@ -110,7 +110,8 @@ def get_models(get_model_kwargs, verbose=True):
loader = csiborgtools.flow.DataLoader(ARGS.simname, nsim_iterator,
cat, fpath, paths,
ksmooth=ARGS.ksmooth)
models[i] = csiborgtools.flow.get_model(loader, **get_model_kwargs)
models[i] = csiborgtools.flow.get_model(
loader, toy_selection=toy_selection[i], **get_model_kwargs)
print(f"\n{'Num. radial steps':<20} {len(loader.rdist)}\n", flush=True)
return models
@ -127,7 +128,7 @@ def get_harmonic_evidence(samples, log_posterior, nchains_harmonic, epoch_num):
def run_model(model, nsteps, nburn, model_kwargs, out_folder, sample_beta,
calculate_evidence, nchains_harmonic, epoch_num, kwargs_print):
calculate_harmonic, nchains_harmonic, epoch_num, kwargs_print):
"""Run the NumPyro model and save output to a file."""
try:
ndata = sum(model.ndata for model in model_kwargs["models"])
@ -148,12 +149,12 @@ def run_model(model, nsteps, nburn, model_kwargs, out_folder, sample_beta,
print(f"{'AIC':<20} {AIC}")
mcmc.print_summary()
if calculate_evidence:
if calculate_harmonic:
print("Calculating the evidence using `harmonic`.", flush=True)
neg_ln_evidence, neg_ln_evidence_err = get_harmonic_evidence(
samples, log_posterior, nchains_harmonic, epoch_num)
print(f"{'-ln(Z)':<20} {neg_ln_evidence}")
print(f"{'-ln(Z) error':<20} {neg_ln_evidence_err}")
print(f"{'-ln(Z_h)':<20} {neg_ln_evidence}")
print(f"{'-ln(Z_h) error':<20} {neg_ln_evidence_err}")
else:
neg_ln_evidence = jax.numpy.nan
neg_ln_evidence_err = (jax.numpy.nan, jax.numpy.nan)
@ -180,8 +181,8 @@ def run_model(model, nsteps, nburn, model_kwargs, out_folder, sample_beta,
grp = f.create_group("gof")
grp.create_dataset("BIC", data=BIC)
grp.create_dataset("AIC", data=AIC)
grp.create_dataset("neg_lnZ", data=neg_ln_evidence)
grp.create_dataset("neg_lnZ_err", data=neg_ln_evidence_err)
grp.create_dataset("neg_lnZ_harmonic", data=neg_ln_evidence)
grp.create_dataset("neg_lnZ_harmonic_err", data=neg_ln_evidence_err)
fname_summary = fname.replace(".hdf5", ".txt")
print(f"Saving summary to `{fname_summary}`.")
@ -206,7 +207,7 @@ def run_model(model, nsteps, nburn, model_kwargs, out_folder, sample_beta,
# Command line interface #
###############################################################################
def get_distmod_hyperparams(catalogue, sample_alpha):
def get_distmod_hyperparams(catalogue, sample_alpha, sample_mag_dipole):
alpha_min = -1.0
alpha_max = 3.0
@ -225,7 +226,7 @@ def get_distmod_hyperparams(catalogue, sample_alpha):
"c_mean": 0., "c_std": 20.0,
"sample_curvature": False,
"a_dipole_mean": 0., "a_dipole_std": 1.0,
"sample_a_dipole": True,
"sample_a_dipole": sample_mag_dipole,
"alpha_min": alpha_min, "alpha_max": alpha_max,
"sample_alpha": sample_alpha,
}
@ -233,7 +234,7 @@ def get_distmod_hyperparams(catalogue, sample_alpha):
return {"e_mu_min": 0.001, "e_mu_max": 1.0,
"dmu_min": -3.0, "dmu_max": 3.0,
"dmu_dipole_mean": 0., "dmu_dipole_std": 1.0,
"sample_dmu_dipole": True,
"sample_dmu_dipole": sample_mag_dipole,
"alpha_min": alpha_min, "alpha_max": alpha_max,
"sample_alpha": sample_alpha,
}
@ -241,6 +242,16 @@ def get_distmod_hyperparams(catalogue, sample_alpha):
raise ValueError(f"Unsupported catalogue: `{ARGS.catalogue}`.")
def get_toy_selection(toy_selection, catalogue):
if not toy_selection:
return None
if catalogue == "SFI_gals":
return [1.221e+01, 1.297e+01, -2.708e-01]
else:
raise ValueError(f"Unsupported catalogue: `{ARGS.catalogue}`.")
if __name__ == "__main__":
paths = csiborgtools.read.Paths(**csiborgtools.paths_glamdring)
out_folder = "/mnt/extraspace/rstiskalek/csiborg_postprocessing/peculiar_velocity" # noqa
@ -251,18 +262,23 @@ if __name__ == "__main__":
# Fixed user parameters #
###########################################################################
nsteps = 1500
nburn = 1000
nsteps = 1000
nburn = 500
zcmb_min = 0
zcmb_max = 0.05
calculate_evidence = False
nchains_harmonic = 10
num_epochs = 30
inference_method = "mike"
num_epochs = 50
inference_method = "bayes"
calculate_harmonic = True if inference_method == "mike" else False
maxmag_selection = None
sample_alpha = True
sample_alpha = False
sample_beta = True
sample_Vmono = False
sample_mag_dipole = False
toy_selection = True
if toy_selection and inference_method == "mike":
raise ValueError("Toy selection is not supported with `mike` inference.") # noqa
if nsteps % nchains_harmonic != 0:
raise ValueError(
@ -272,10 +288,12 @@ if __name__ == "__main__":
"zcmb_min": zcmb_min,
"zcmb_max": zcmb_max,
"maxmag_selection": maxmag_selection,
"calculate_evidence": calculate_evidence,
"calculate_harmonic": calculate_harmonic,
"nchains_harmonic": nchains_harmonic,
"num_epochs": num_epochs,
"inference_method": inference_method}
"inference_method": inference_method,
"sample_mag_dipole": sample_mag_dipole,
"toy_selection": toy_selection}
print_variables(main_params.keys(), main_params.values())
calibration_hyperparams = {"Vext_min": -1000, "Vext_max": 1000,
@ -290,7 +308,7 @@ if __name__ == "__main__":
distmod_hyperparams_per_catalogue = []
for cat in ARGS.catalogue:
x = get_distmod_hyperparams(cat, sample_alpha)
x = get_distmod_hyperparams(cat, sample_alpha, sample_mag_dipole)
print(f"\n{cat} hyperparameters:")
print_variables(x.keys(), x.values())
distmod_hyperparams_per_catalogue.append(x)
@ -301,7 +319,11 @@ if __name__ == "__main__":
get_model_kwargs = {"zcmb_min": zcmb_min, "zcmb_max": zcmb_max,
"maxmag_selection": maxmag_selection}
models = get_models(get_model_kwargs, )
toy_selection = [get_toy_selection(toy_selection, cat)
for cat in ARGS.catalogue]
models = get_models(get_model_kwargs, toy_selection)
model_kwargs = {
"models": models,
"field_calibration_hyperparams": calibration_hyperparams,
@ -312,5 +334,5 @@ if __name__ == "__main__":
model = csiborgtools.flow.PV_validation_model
run_model(model, nsteps, nburn, model_kwargs, out_folder,
calibration_hyperparams["sample_beta"], calculate_evidence,
calibration_hyperparams["sample_beta"], calculate_harmonic,
nchains_harmonic, num_epochs, kwargs_print)

View file

@ -39,7 +39,7 @@ fi
# for simname in "Lilow2024" "CF4" "CF4gp" "csiborg1" "csiborg2_main" "csiborg2X"; do
for simname in "Carrick2015"; do
for catalogue in "CF4_GroupAll"; do
for catalogue in "SFI_gals"; do
# for catalogue in "CF4_TFR_i"; do
# for ksim in 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20; do
for ksim in "none"; do

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@ -0,0 +1,60 @@
from argparse import ArgumentParser, ArgumentTypeError
def parse_args():
parser = ArgumentParser()
parser.add_argument("--device", type=str, default="cpu",
help="Device to use.")
return parser.parse_args()
ARGS = parse_args()
# This must be done before we import JAX etc.
from numpyro import set_host_device_count, set_platform # noqa
set_platform(ARGS.device) # noqa
from jax import numpy as jnp # noqa
import numpy as np # noqa
import csiborgtools # noqa
from scipy.stats import multivariate_normal # noqa
def get_harmonic_evidence(samples, log_posterior, nchains_harmonic, epoch_num):
"""Compute evidence using the `harmonic` package."""
data, names = csiborgtools.dict_samples_to_array(samples)
data = data.reshape(nchains_harmonic, -1, len(names))
log_posterior = log_posterior.reshape(nchains_harmonic, -1)
return csiborgtools.harmonic_evidence(
data, log_posterior, return_flow_samples=False, epochs_num=epoch_num)
ndim = 250
nsamples = 100_000
nchains_split = 10
loc = jnp.zeros(ndim)
cov = jnp.eye(ndim)
gen = np.random.default_rng()
X = gen.multivariate_normal(loc, cov, size=nsamples)
samples = {f"x_{i}": X[:, i] for i in range(ndim)}
logprob = multivariate_normal(loc, cov).logpdf(X)
neg_lnZ_laplace, neg_lnZ_laplace_error = csiborgtools.laplace_evidence(
samples, logprob, nchains_split)
print(f"neg_lnZ_laplace: {neg_lnZ_laplace} +/- {neg_lnZ_laplace_error}")
neg_lnZ_harmonic, neg_lnZ_harmonic_error = get_harmonic_evidence(
samples, logprob, nchains_split, epoch_num=30)
print(f"neg_lnZ_harmonic: {neg_lnZ_harmonic} +/- {neg_lnZ_harmonic_error}")