model.py 文件源码

def ests_ll_exact(self, params):
        """
        Calculate the loglikelihood given model parameters `params`.

        This method uses an exact integral and returns exact ll values, i.e.
        it does not use quadrature to approximate the integral.
        """
        mu, gamma, err = np.split(params, 3)
        d = self.num2 - mu
        q = self.w2 / err**2
        r = d * q

        f = self.w2 @ (2 * np.log(abs(err)) + LOG2PI)
        a = q @ gamma**2
        b = r @ gamma
        c = nsum_row(d * r)

        return .5 * (b * b / (a+1) - c - f - np.log1p(a))