}
	if testing.Short() {
		// Depends on syslog daemon running, and sometimes it's not.
		t.Skip("skipping syslog test during -short")
	}

	s, err := New(LOG_INFO|LOG_USER, "the_tag")
	if err != nil {
		if err.Error() == "Unix syslog delivery error" {
			t.Skip("skipping: syslogd not running")
		}
		t.Fatalf("New() failed: %s", err)
	}
	// Don't send any messages.
	s.Close()
}

    // Take Difference of both estimates: (f(theta + eps) - f(theta - eps)).
    TF_RETURN_IF_ERROR(
        ops::Sub(ctx, fPlus.get(), fMinus.get(), f_outputs, "sub_top"));
    AbstractTensorHandlePtr fDiff(f_outputs[0]);

    // Calculate using the difference quotient definition:
    // (f(theta + eps) - f(theta - eps)) / (2 * eps).
    TF_RETURN_IF_ERROR(

}

// ExampleExp computes Euler's identity.
func ExampleExp() {
	fmt.Printf("%.1f", cmplx.Exp(1i*math.Pi)+1)
	// Output: (0.0+0.0i)
}

func ExamplePolar() {
	r, theta := cmplx.Polar(2i)
	fmt.Printf("r: %.1f, θ: %.1f*π", r, theta/math.Pi)
	// Output: r: 2.0, θ: 0.5*π

	}
	modulus := Abs(x)
	if modulus == 0 {
		return complex(0, 0)
	}
	r := math.Pow(modulus, real(y))
	arg := Phase(x)
	theta := real(y) * arg
	if imag(y) != 0 {
		r *= math.Exp(-imag(y) * arg)
		theta += imag(y) * math.Log(modulus)
	}
	s, c := math.Sincos(theta)
	return complex(r*c, r*s)