def eval(self, mu, var):
        """
        ported from GPML toolbox - not used.
        """
        lp, _, _ = self.moment_match(1, mu, var)
        p = np.exp(lp)
        ymu = 2 * p - 1
        yvar = 4 * p * (1 - p)
        return lp, ymu, yvar