hyper.py 文件源码

def convergence_statement(self):
        """ Return a condition on z under which the series converges. """
        from sympy import And, Or, re, Ne, oo
        R = self.radius_of_convergence
        if R == 0:
            return False
        if R == oo:
            return True
        # The special functions and their approximations, page 44
        e = self.eta
        z = self.argument
        c1 = And(re(e) < 0, abs(z) <= 1)
        c2 = And(0 <= re(e), re(e) < 1, abs(z) <= 1, Ne(z, 1))
        c3 = And(re(e) >= 1, abs(z) < 1)
        return Or(c1, c2, c3)