Examples of random() in custom distribution?

Questions
20

Fix the code, now work as expected. Thanks!

code

import pymc as pm
import matplotlib.pyplot as plt

def logp_skewt(value, nu, mu, sigma, alpha, *args, **kwargs):
    return (
        pm.math.log(2) + 
        pm.logp(pm.StudentT.dist(nu, mu=mu, sigma=sigma), value) + 
        pm.logcdf(pm.StudentT.dist(nu, mu=mu, sigma=sigma), alpha*value) - 
        pm.math.log(sigma)
    )

with pm.Model() as model:
    skewt = pm.CustomDist('likelihood', 1, 0, 3, -10, logp=logp_skewt)
    model_trace = pm.sample(
        nuts_sampler="numpyro",
        draws=10_000,
        chains=1,
    )
    
samples = model_trace.posterior.likelihood.to_numpy()

plt.hist(samples[(samples < 30) & (samples > -100)], bins=100, density=True)
plt.show()
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