def getLimits(self, alpha, upper=True):
        """ Evaluate the limits corresponding to a C.L. of (1-alpha)%.

        Parameters
        ----------
        alpha :  float
           limit confidence level.
        upper :  bool
           upper or lower limits.

        returns an array of values, one for each energy bin
        """
        limit_vals = np.ndarray((self._nx))

        for i in range(self._nx):
            limit_vals[i] = self._loglikes[i].getLimit(alpha, upper)

        return limit_vals