Question

我正在尝试使用递归创建一个程序，它会像这样创建一个H树（这是1阶）： H tree

零阶H树只是一个以中心点为中心的H，同一条线的H的所有三条线都是长的该函数将接收一个乌龟对象，一个表示树顺序的整数，一个中心点和该行的长度。如果顺序大于零，则将在步骤1中绘制的H的四个端点中的每一个中心绘制四个较小阶（阶数-1）和较小长度线（线长度/ 2）的H树。

到目前为止，我有这个：

import turtle

def drawHTree(length, depth):
    if depth > 0:
        turtle.forward(length / 2)
        turtle.right(90)
        turtle.forward(length / 2)
        turtle.left(90)

        drawHTree(length / 2, depth - 1)

        turtle.left(90)
        turtle.forward(length)
        turtle.right(90)

        drawHTree(length / 2, depth - 1)

        turtle.right(90)
        turtle.forward(length / 2)
        turtle.right(90)
        turtle.forward(length)
        turtle.left(90)
        turtle.forward(length / 2)
        turtle.left(90)

        drawHTree(length / 2, depth - 1)

        turtle.left(90)
        turtle.forward(length)
        turtle.right(90)

        drawHTree(length / 2, depth - 1)

        turtle.right(90)
        turtle.forward(length / 2)
        turtle.left(90)
        turtle.forward(length / 2)

window = turtle.Screen()
drawHTree(200,2)

任何帮助或建议都会很棒！谢谢！

Answer 1

如果您修复缩进，上面的（原始）代码是正确的。你似乎有关键原则：首先得到它来绘制 H ;确保函数离开乌龟的位置与调用函数时的位置完全相同。以下是我对您的代码的修订，以解决一些样式问题，获取深度/订单号以正确匹配所需的图形并匹配所述的API：

该函数将接收一个乌龟对象，一个表示该对象的整数树顺序，中心点和线的长度

from turtle import Turtle, Screen

def drawHTree(turtle, order, center, length):

    if order < 0:
        return

    if center is not None:
        turtle.up()
        turtle.goto(center)
        turtle.down()

    turtle.forward(length / 2)
    turtle.right(90)
    turtle.forward(length / 2)
    turtle.left(90)

    drawHTree(turtle, order - 1, None, length / 2)

    turtle.left(90)
    turtle.forward(length)
    turtle.right(90)

    drawHTree(turtle, order - 1, None, length / 2)

    turtle.right(90)
    turtle.forward(length / 2)
    turtle.right(90)
    turtle.forward(length)
    turtle.left(90)
    turtle.forward(length / 2)
    turtle.right(90)

    drawHTree(turtle, order - 1, None, length / 2)

    turtle.right(90)
    turtle.forward(length)
    turtle.right(90)

    drawHTree(turtle, order - 1, None, length / 2)

    turtle.right(90)
    turtle.forward(length / 2)
    turtle.left(90)
    turtle.forward(length / 2)  # always leave the turtle where you found it!

yertle = Turtle()

drawHTree(yertle, 2, (0, 0), 200)

screen = Screen()

screen.exitonclick()

<强>产生

使用乌龟的递归H树

1 个答案: