def gbayes(x0, g_est, sigma):
Kx = norm().pdf((g_est[<NUM_LIT:0>] - x0) / sigma)<EOL>post = Kx * g_est[<NUM_LIT:1>]<EOL>post /= sum(post)<EOL>return sum(post * g_est[<NUM_LIT:0>])<EOL>
Estimate Bayes posterior with Gaussian noise [Efron2014]_.

Parameters
----------
x0: ndarray
    an observation
g_est: float
    a prior density, as returned by gfit
sigma: int
    noise estimate

Returns
-------
An array of the posterior estimate E[mu | x0]