def round(self, eps=1e-14, rmax=100000):
        """ Computes an approximation to a
            TT-matrix in with accuracy EPS
        """
        c = matrix()
        c.tt = self.tt.round(eps, rmax)
        c.n = self.n.copy()
        c.m = self.m.copy()
        return c
Computes an approximation to a
            TT-matrix in with accuracy EPS