def predefined(self, y0, xout, params=(), **kwargs):
        """ Integrate with user chosen output.

        Parameters
        ----------
        integrator : str
            See :meth:`integrate`.
        y0 : array_like
            See :meth:`integrate`.
        xout : array_like
        params : array_like
            See :meth:`integrate`.
        \*\*kwargs:
            See :meth:`integrate`

        Returns
        -------
        Length 2 tuple : (yout, info)
            See :meth:`integrate`.
        """
        xout, yout, info = self.integrate(xout, y0, params=params,
                                          force_predefined=True, **kwargs)
        return yout, info