"""BetaUnivariate module."""
import numpy as np
from scipy.stats import beta
from copulas.univariate.base import BoundedType, ParametricType, ScipyModel
[docs]class BetaUnivariate(ScipyModel):
"""Wrapper around scipy.stats.beta.
Documentation: https://docs.scipy.org/doc/scipy/reference/generated/scipy.stats.beta.html
"""
PARAMETRIC = ParametricType.PARAMETRIC
BOUNDED = BoundedType.BOUNDED
MODEL_CLASS = beta
def _fit_constant(self, X):
self._params = {
'a': 1.0,
'b': 1.0,
'loc': np.unique(X)[0],
'scale': 0.0,
}
def _fit(self, X):
loc = np.min(X)
scale = np.max(X) - loc
a, b, loc, scale = beta.fit(X, loc=loc, scale=scale)
self._params = {
'loc': loc,
'scale': scale,
'a': a,
'b': b
}
def _is_constant(self):
return self._params['scale'] == 0
def _extract_constant(self):
return self._params['loc']