New package structure

[mberaha]

I split the Pybmix package into 2: pybmixlib and pybmix

The former one provides access to the AlgorithmWrapper, and is build with pybind11. It does not contain any pure python code.

The latter one contains the protobuf messages and the pure python code.

They must be installed separately:

cd pybmixlib
python3 -m pip install -e .
cd ..
python3 -m pip install -e .

I tested that things work by having this file in the main directory (I named it test_run.py):

import numpy as np
import matplotlib.pyplot as plt

from pybmix.core.mixing import DirichletProcessMixing, StickBreakMixing
from pybmix.core.hierarchy import UnivariateNormal
from pybmix.core.mixture_model import MixtureModel

np.random.seed(2021)


def sample_from_mixture(weigths, means, sds, n_data):
    n_comp = len(weigths)
    clus_alloc = np.random.choice(np.arange(n_comp), p=[0.5, 0.5], size=n_data)
    return np.random.normal(loc=means[clus_alloc], scale=sds[clus_alloc])

y = sample_from_mixture(
    np.array([0.5, 0.5]), np.array([-3, 3]), np.array([1, 1]), 200)

mixing = DirichletProcessMixing(total_mass=5)
hierarchy = UnivariateNormal()
hierarchy.make_default_fixed_params(y, 2)
mixture = MixtureModel(mixing, hierarchy)

mixture.run_mcmc(y, algorithm="Neal2", niter=2000, nburn=1000)

Then

python3 -m test_run

Initializing... Done
Running Neal2 algorithm with NNIG hierarchies, DP mixing...
[============================================================] 100% 0.457s
Done