星系螺旋模型

GeoGebra 命令及参数

1. CurveCartesian(((sp_1 * ℯ^((θ * cot(sp_2)))); θ), θ, 0, sp_3) → c
2. Rotate(c, 180° + α, A) → c'
3. Rotate(c, 0*° + α, A) → c'_1
4. Sequence(c'(i) + (Random[(v_{min} * 10), (v_{max} * 10)] / 10, Random[(v_{min} * 10), (v_{max} * 10)] / 10), i, 0, sp_3, (2 * sp_3 / (n - 1))) → L_3
5. Sequence(c'_1(i), i, 0, sp_3, n) → L_2
6. Sequence(c'(i), i, 0, sp_3, n) → L_1
7. Length(L_3) → s1
8. Length(L_3) → s2
9. Sequence(c'_1(i) + (Random[(v_{min} * 10), (v_{max} * 10)] / 10, Random[(v_{min} * 10), (v_{max} * 10)] / 10), i, 0, sp_3, (2 * sp_3 / (n - 1))) → L_4