映射图范例：从RP1到RP1

GeoGebra 命令及参数

1. Line(A, (1, 0, 0)) → a
2. Circle(a, B) → c
3. Circle(a, C) → d
4. Point(c) → P_x
5. Line((0, -1, 0), P_x) → b
6. Line(A, (0, 0, 1)) → e
7. Line(B, e) → tan_x
8. Intersect(tan_x, b) → T_x
9. Line(T_{f(x)}, Q_∞) → g
10. Intersect(g, d) → E, Q_{f(x)}
11. Vector(P_x, Q_{f(x)}) → a_f
12. Textfield(f) → inputBox1
13. Point(tan_x) → T_{x0}
14. Line(T_{x0}, P_∞) → h
15. Intersect(h, c) → F, P_{x0}
16. Line(T_{f(x0)}, Q_∞) → i
17. Intersect(i, d, 2) → Q_{f(x0)}
18. Vector(P_{x0}, Q_{f(x0)}) → u