So this is the simple code:
#%%
import numpy as np;
import matplotlib.pyplot as plt;
import pymc3 as pm;
#%%
observed_data=np.random.normal(3,1,20)
basic_model = pm.Model()
with basic_model:
# Priors for unknown model parameters
a = pm.Normal('a', 5, 5)
s=pm.HalfNormal('sigma_lik',sd=5)
Y_obs = pm.Normal('Y_obs', mu=a, sd=s, observed=observed_data)
trace=pm.sample( 10000, tune= 2000, njobs=1)
pm.traceplot(trace)
For njobs=1 it is what I get:
C:\ProgramData\Anaconda3\lib\site-packages\h5py_init_.py:34: FutureWarning: Conversion of the second argument of issubdtype from float to np.floating is deprecated. In future, it will be treated as np.float64 == np.dtype(float).type.
from .conv import register_converters as register_converters
Auto-assigning NUTS sampler…
Initializing NUTS using jitter+adapt_diag…
Sequential sampling (2 chains in 1 job)
NUTS: [sigma_lik_log, a]
100%|██████████| 12000/12000 [00:18<00:00, 660.53it/s]
100%|██████████| 12000/12000 [00:10<00:00, 1112.94it/s]
The model with njobs=1 was fast and done in few seconds. With njobs=2 it is still running and chain apparently does not even start. I provide you the screenshot.
