def METHOD_NAME(self, x):
    """Multivariate normal log-likelihood."""
    ret = -0.5 * np.dot(
        (x - self.mean), np.dot(self.cov_inv,
                                (x - self.mean))) + self.lnorm
    # notice here we overwrite the input array just to test
    # that this is not a problem
    x[:] = -np.ones(len(x))
    return ret