用遞歸和Turtle庫繪制八進制的雪花。以下是遞歸深度從1~5的八面形雪花：

除了通過遞歸深度停止遞歸，還可以在半徑小于特定大小時停止遞歸。以下八面形雪花是通過将半徑遞歸的阈值設置為10生成的。現在你可以看到所有的八邊形都有相同的尺寸

import turtle from turtle import * import math import random # 以指定的中心，畫八面形 def octagon(x, y, r): # x,y is the center up() goto(x, y) seth(90) fd(r) left(180 - 135 / 2) down() begin_fill() edgeSize = 2 * r * math.sin(math.radians(45 / 2)) for _ in range(8): fd(edgeSize) left(45) end_fill() # 畫八面形雪花 def octaflake(x, y, r, n): # 根據遞歸深度（recursion depths）控制何時退出遞歸 # if n ==1: # octagon(x, y, r) # return # 根據八面形的半徑控制，當半徑小于10時，退出遞歸 if r < 10: octagon(x, y, r) return r2 = r / (1 1 / math.tan(math.radians(45 / 2))) octaflake(x, y, r - 2 * r2, n - 1) direction = 90 for _ in range(8): up() goto(x, y) seth(direction) fd(r - r2) octaflake(xcor(), ycor(), r2, n - 1) direction = 45 def main(): screen = Screen() screen.setup(800, 600) screen.title('cloudcloder出品--畫雪花') bgcolor('royal blue') fillcolor('white') pencolor('steel blue') speed(0) screen.tracer(0, 0) octaflake(-200, -200, 70, 1) octaflake(-50, -50, 80, 2) octaflake(-190, 100, 50, 3) octaflake(200, 100, 80, 4) octaflake(-190, 200, 50, 3) octaflake(-190, 0, 50, 3) octaflake(180, -140, 120, 5) screen.update() done() if __name__ == "__main__": hideturtle() up() goto(-260, 270) write("今日頭條-cloudcoder出品", align='left', font=('fangsong', 14, 'normal')) showturtle() main()