Пример #1
0
def loglik_pos(batch_data, list_type, theta, normalization_params):
    # Log-normal distribution
    output = dict()
    epsilon = 1e-3

    # Data outputs
    data_mean_log, data_var_log = normalization_params
    data_var_log = torch.clamp(data_var_log, epsilon, np.inf)

    data, missing_mask = batch_data
    data_log = torch.log(1.0 + data)
    missing_mask = missing_mask.float()

    est_mean, est_var = theta
    est_var = torch.clamp(torch.nn.Softplus()(est_var), epsilon, 1.0)

    # Affine transformation of the parameters
    est_mean = torch.sqrt(data_var_log) * est_mean + data_mean_log
    est_var = data_var_log * est_var

    # Compute loglik
    log_p_x = -0.5 * torch.sum(torch.pow(data_log - est_mean, 2) / est_var, 1) \
              - 0.5 * torch.sum(torch.log(2 * np.pi * est_var), 1) - torch.sum(data_log, 1)
    log_normal = td.LogNormal(est_mean, torch.sqrt(est_var))
    # log_p_x = log_normal.log_prob(data).sum(1)  ##

    output['log_p_x'] = torch.mul(log_p_x, missing_mask)
    output['log_p_x_missing'] = torch.mul(log_p_x, 1.0 - missing_mask)
    output['params'] = [est_mean, est_var]
    output['samples'] = log_normal.rsample() - 1.0  # -1.0 TODO???
    # output['samples'] = torch.clamp(
    #     torch.exp(td.Normal(est_mean, torch.sqrt(est_var)).rsample()) - 1.0, 0, 1e20)

    return output
Пример #2
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    def gen_data(self):
        # sample overall relative abundances of ASVs from a Dirichlet distribution
        self.ASV_rel_abundance = tdist.Dirichlet(torch.ones(
            self.numASVs)).sample()

        # sample spatial embedding of ASVs
        self.w = torch.zeros(self.numASVs, self.D)
        w_prior = tdist.MultivariateNormal(torch.zeros(self.D),
                                           torch.eye(self.D))

        for o in range(0, self.numASVs):
            self.w[o, :] = w_prior.sample()

        self.data = torch.zeros(self.numParticles, self.numASVs)

        num_nonempty = 0

        mu_prior = tdist.MultivariateNormal(torch.zeros(self.D),
                                            torch.eye(self.D))
        rad_prior = tdist.LogNormal(torch.tensor([self.mu_rad]),
                                    torch.tensor([self.mu_std]))

        # replace with neg bin prior
        num_reads_prior = tdist.Poisson(
            torch.tensor([self.avgNumReadsParticle]))

        while (num_nonempty < self.numParticles):
            # sample center
            mu = mu_prior.sample()
            rad = rad_prior.sample()

            zr = torch.zeros(1, self.numASVs, dtype=torch.float64)
            for o in range(0, self.numASVs):
                p = mu - self.w[o, :]
                p = torch.pow(p, 2.0) / rad
                p = (torch.sum(p)).sqrt()
                zr[0, o] = unitboxcar(p, 0.0, 2.0, self.step_approx)

            if torch.sum(zr) > 0.95:
                particle = Particle(mu, self)
                particle.zr = zr
                self.particles.append(particle)

                # renormalize particle abundances
                rn = self.ASV_rel_abundance * zr
                rn = rn / torch.sum(rn)

                # sample relative abundances for particle
                part_rel_abundance = tdist.Dirichlet(rn * self.conc).sample()

                # sample number of reads for particle
                # (replace w/ neg bin instead of Poisson)
                num_reads = num_reads_prior.sample().long().item()
                particle.total_reads = num_reads

                particle.reads = tdist.Multinomial(
                    num_reads, probs=part_rel_abundance).sample()

                num_nonempty += 1
Пример #3
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    def decode_x(self, w, z):
        params = self.decoder_x(torch.cat((w, z), dim=-1))

        px_wz = []
        samples = []

        for indices in self.likelihood_partition:
            data_type = self.likelihood_partition[indices]

            params_subset = params[:, indices[0]:(indices[1] + 1)]

            if data_type == 'real':
                cov_diag = self.likelihood_params['lik_var'] * torch.ones_like(
                    params_subset).to(self.device)

                dist = D.Normal(loc=params_subset, scale=cov_diag.sqrt())

            elif data_type == 'categorical':
                dist = D.OneHotCategorical(logits=params_subset)
            elif data_type == 'binary':
                dist = D.Bernoulli(logits=params_subset)
            elif data_type == 'positive':
                lognormal_var = self.likelihood_params[
                    'lik_var_lognormal'] * torch.ones_like(params_subset).to(
                        self.device)

                dist = D.LogNormal(loc=params_subset,
                                   scale=lognormal_var.sqrt())
            elif data_type == 'count':
                positive_params_subset = F.softplus(params_subset)
                dist = D.Poisson(rate=positive_params_subset)
            elif data_type == 'binomial':
                num_trials = self.likelihood_params['binomial_num_trials']
                dist = D.Binomial(total_count=num_trials, logits=params_subset)
            elif data_type == 'ordinal':
                h = params_subset[:, 0:1]
                thetas = torch.cumsum(F.softplus(params_subset[:, 1:]), axis=1)

                prob_lessthans = torch.sigmoid(thetas - h)
                probs = torch.cat((prob_lessthans, torch.ones(len(prob_lessthans), 1)), axis=1) - \
                        torch.cat((torch.zeros(len(prob_lessthans), 1), prob_lessthans), axis=1)

                dist = D.OneHotCategorical(probs=probs)
            else:
                raise NotImplementedError

            samples.append(dist.sample())
            px_wz.append(dist)

        sample_x = torch.cat(samples, axis=1)

        return params, sample_x, px_wz
Пример #4
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    def dist(
        self,
        batch: dict[str, Union[torch.Tensor, list[torch.Tensor]]],
    ) -> distributions.Distribution:
        """Возвращает распределение доходности."""
        logits, mean, std = self(batch)

        try:
            weights_dist = distributions.Categorical(logits=logits)
        except ValueError:
            raise GradientsError(
                f"Ошибка при обновлении градиентов: NaN in Categorical distribution"
            )

        comp_dist = distributions.LogNormal(mean, std)

        return distributions.MixtureSameFamily(weights_dist, comp_dist)
Пример #5
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# sample embedding of OTUs
w = torch.zeros(O, D)
w_prior = tdist.MultivariateNormal(torch.zeros(D), torch.eye(D))

for o in range(0, O):
    w[o, :] = w_prior.sample()

# hyperparameters for particle radius
#eta_1 = 1.0
#eta_2 = 2.0
#rad_prior = tdist.Gamma(torch.tensor([eta_1]), torch.tensor([eta_2]))
#rad = rad_prior.sample()*4.0
#rad = rad * rad
mu_rad = numpy.log(1.0)
mu_std = 1.0
rad_prior = tdist.LogNormal(torch.tensor([mu_rad]), torch.tensor([mu_std]))
#rad = rad_prior.sample()
rad = torch.tensor([1.0])

# sample particle center
mu_prior = tdist.MultivariateNormal(torch.zeros(D), torch.eye(D))
mu = mu_prior.sample()

print('mu=', mu)
print('rad=', rad)

# sample indicator as to whether OTUs occur in the particle
#z = torch.zeros(O,1,dtype=torch.int64)
zr = torch.zeros(O, 1, dtype=torch.float64)

# annealing parameter for unit step approximation
Пример #6
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def lognormal_log_pdf(x, mu, logvar):
    scale = 0.5 * torch.exp(logvar)
    p_dist = dist.LogNormal(mu, scale)
    logprob = p_dist.log_prob(x)
    return torch.sum(logprob, dim=1)
Пример #7
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from matplotlib import pyplot as plt
import torch
import torch.distributions as ds

# Sample synthetic data from a heavitailed distribution for the sizes
# Sample random ids from 1 to 1000 for the packet senders
N_SAMPLES = 100000000
N_IDS = 10000
FNAME = 'trace/generated_data_1e5_1e9'
size_dist = ds.LogNormal(torch.tensor([0.0]), torch.tensor([2.0]))
id_dist = ds.Uniform(torch.tensor([0]).float(), torch.tensor([N_IDS]).float())

sizes = []
ids = []

for index in range(N_SAMPLES):
    if index % 1000000 == 0:
        print(index)
    packet_size = int(size_dist.sample().long().numpy()[0] + 1)
    packet_id = int(id_dist.sample().long().numpy()[0])
    sizes.append(packet_size)
    ids.append(packet_id)

arr = [str(a) + " " + str(b) + "\n" for a, b in zip(sizes, ids)]
with open(FNAME, 'w') as f:
    f.write("".join(arr))
Пример #8
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"""

from math import comb

import matplotlib.pyplot as plt
import numpy as np
import pandas as pd
import torch
import torch.nn as nn
import torch.nn.functional as F
import torch.distributions as D
import torch.optim as optim
from torch.utils.data import Dataset, DataLoader
from tqdm import trange

m = D.LogNormal(torch.tensor([0.0]), torch.tensor([1.0]))

m.log_prob(torch.tensor([2.]))

# GLOBAL
SEED = 42
VERBOSITY = 0

# VAE
NUM_EPOCHS_TUNE = 200
NUM_EPOCHS = 500
HIDDEN_DIM = 64
Z_PRIOR_VAR = 0.5**2
X_POST_VAR = 0.1**2

Пример #9
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    def sample_logp(self, N, I, noise=None):
        
        max_tau = self.tau_count
        burnin = self.burnin 
        logp0  = 0.0
        
        T = len(I)
        P     = self.P.exp()
        N_0   = self.N_0.exp()
        s_d   = self.s_d.exp()
        s_p   = self.s_p.exp()
        delta = self.delta.exp()
        
        p_tau = td.Categorical(logits=self.tau_logits)
        tau   = p_tau.sample([N])
        logp0 = logp0 + p_tau.log_prob(tau)

        tau   = tau + 1
            
        #tau = self.tau_logits.softmax(0)
        
        p_et = td.Gamma(1 / s_p**2, 1 / s_p**2)
        et = p_et.sample([N, T+burnin])
        logp0 = logp0 + p_et.log_prob(et).sum(1)

        p_epsilont = td.Gamma(1 / s_d**2, 1 / s_d**2)
        epsilont = p_epsilont.sample([N, T+burnin])
        logp0 = logp0 + p_epsilont.log_prob(epsilont).sum(-1)
        
                
        #z = self.z_0.exp().expand(N)
        zs = torch.zeros(N, max_tau+burnin+T, dtype=P.dtype, device=P.device)
        zs[torch.arange(N),:max_tau] = self.z_0.sigmoid()
        
        z = zs[torch.arange(N),max_tau-1]    
        for t in torch.arange(max_tau, T+burnin+max_tau):
        
            ztmtau = zs[torch.arange(N), t-tau]
            # print("----")
            # print(zs[:,:t+1])
            # print(tau_t)
            # print(ztmtau)
            # tstart = max(0, t+1-len(tau))
            # ztmtau = zs[torch.arange(N), tstart:t+1] @ tau[:min(t,len(tau))+1]
            z = P * ztmtau * (-ztmtau / N_0).exp() * et[:,t-max_tau] + z * (-delta * epsilont[:,t-max_tau]).exp()
            
            pz = td.LogNormal(z.log(), self.rand_std.exp())
            z  = pz.sample([])
            logp0   = logp0 + pz.log_prob(z)
            zs[:,t] = z
        
        xs = zs[:, -T:].detach()
        
        '''
        if noise is None:
            noise_dist = td.Normal(xs, self.noise_std.exp())
        else:
            noise_dist = td.Normal(xs, max(noise, 1e-6))
        xs = noise_dist.sample([])
        xs = xs.reshape(N, -1)
        nat = Likelihoods.gaussian_nat(noise_dist)
        norm = Likelihoods.gaussian_norm(noise_dist)
        return (tau, et, epsilont, zs), xs, norm - logp0, nat
        '''

        return (tau, et, epsilont, zs), xs, -logp0, torch.zeros(N,T*2,dtype=xs.dtype,device=xs.device)
Пример #10
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 def entropy(self):
     return dists.LogNormal(self.loc, self.scale).entropy()
Пример #11
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 def sample(self, batch_size):
     return dists.LogNormal(self.loc, self.scale).rsample((batch_size, ))
Пример #12
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 def log_prob(self, value):
     return dists.LogNormal(self.loc, self.scale).log_prob(value).sum(-1)