乌龟放慢了较大的图纸

Question

我创建了一些代码来模拟Sierpinski的三角形。为此，在我的代码中，我设置了它，以便它可以模拟三角形上的任意数量，但是我注意到将其增加到一个数量，最终是乌龟花费大量时间增加的时间它继续。

我用100 000点进行了样本输出，这是我得到的

0% done
Time since last update: 0.0019948482513427734
5.0% done
Time since last update: 1.2903378009796143
10.0% done
Time since last update: 1.8589198589324951
15.000000000000002% done
Time since last update: 2.325822114944458
20.0% done
Time since last update: 2.9351391792297363
25.0% done
Time since last update: 3.4773638248443604
30.0% done
Time since last update: 4.152036190032959
35.0% done
Time since last update: 4.7314231395721436
40.0% done
Time since last update: 5.260996103286743
44.99999999999999% done
Time since last update: 5.988528490066528
49.99999999999999% done
Time since last update: 6.804485559463501
54.99999999999999% done
Time since last update: 7.768667221069336
60.0% done
Time since last update: 8.379971265792847
65.0% done
Time since last update: 8.995774745941162
70.0% done
Time since last update: 15.876121282577515
75.00000000000001% done
Time since last update: 17.292492151260376
80.00000000000001% done
Time since last update: 29.57323122024536
85.00000000000001% done
Time since last update: 65.96741080284119
90.00000000000003% done
Time since last update: 148.21749567985535
95.00000000000003% done

代码运行该程序的主要循环的是

t = turtle.Turtle()
t.penup()
curr_time = time()
for x in range(iterations):
    #The code will take a while should the triangle be large, so this will give its % completion
    if x / iterations > percent_done:
        print(percent_done * 100, r"% done", sep='')
        percent_done += 0.05
        window.update()
        print(f"Time since last update:\t{time() - curr_time}")
        curr_time = time()

    c = determine_point(t, init_c)

    make_point(t, c)

dester_point，而make_point根本不迭代，所以我找不到乌龟慢速的原因大量下降。为什么乌龟会随着更多的积分而放慢脚步？ （屏幕示踪剂已经设置为（0,0），并且代码本身按预期的

要点工作：

def make_point(turt: turtle.Turtle, point):
    '''
    Basically does turt.goto(*point) where point is a list of length 2, then places a dot at that place

    I did not use goto because I forgot what the function was, and instead of doing a 2 second google search to find out,
    I did a 15 second google search to find out how to set the angle of the turtle, and use trigonometry and pythagorean
    theorem in order to move the turt to the right position
    '''
    if point[0] != turt.xcor():
        y = point[1] - turt.ycor()
        x = point[0] - turt.xcor()
        if x > 0:
            turt.setheading(math.degrees(math.atan(y / x)))
        else:
            turt.setheading(math.degrees(math.pi + math.atan(y / x)))
    else:
        turt.setheading(0 if point[1] < turt.ycor() else 180)
    turt.fd(pythag(turt.xcor(), turt.ycor(), point[0], point[1]))
    turt.dot(3)

dester_point：

def determine_point(turt: turtle.Turtle, initial_cords):
    '''
    Returns the midpoint between the turt's current coordinates and a random one of the of the 3 starting points
    '''
    coord = initial_cords[random.randint(0, 2)]
    result = []
    result.append((coord[0] - turt.xcor()) / 2 + turt.xcor())
    result.append((coord[1] - turt.ycor()) / 2 + turt.ycor())
    return result

pythag：

def pythag(a, b, x, y):
    '''
    Does pythagorean theorem to find the length between 2 points
    '''
    return math.sqrt((x - a) ** 2 + (y - b) ** 2)

Answer 1

尽管您的代码不需要每次迭代的更多资源，但您的 program 这样做是因为它是在可以的库的顶部构建的。乌龟和Tkinter都是如此。

尽管我们认为Turtle dot（）是提起 dead 墨水，而不是可以选择性地删除的 stamp ，与基础的TKINTER Graphics相比，所有内容都是 live 墨水，并添加到其（re）显示列表中。

我无法完全删除每次迭代的时间增加，但是通过优化代码，我相信我将其减少到不再是问题。我的一些优化：将乌龟放入 readians 模式以避免呼叫Math.degrees（）;将呼叫减少到乌龟，例如。通过position（）而不是调用XCOR（）和ycor（），通过position（）将x和y进行一个步骤。关闭Turtle的撤消缓冲区，因为它会保留越来越多的图形命令列表：

from turtle import Screen, Turtle
from time import time
from random import choice
from math import sqrt, atan, pi

iterations = 100_000
init_c = [(300, -300), (300, 300), (-300, -300)]

def make_point(t, point):
    '''
    Basically do turtle.goto(*point) where point is a list of length 2,
    then places a dot at that place

    I did not use goto() because I forgot what the function was, and instead
    of doing a 2 second google search to find out, I did a 15 second google
    search to find out how to set the angle of the turtle, and use trigonometry
    and pythagorean theorem in order to move the turtle to the right position
    '''

    x, y = t.position()

    if point[0] != x:
        dx = point[0] - x
        dy = point[1] - y

        if dx > 0:
            t.setheading(atan(dy / dx))
        else:
            t.setheading(pi + atan(dy / dx))
    else:
        t.setheading(0 if point[1] < y else pi)

    t.forward(pythag(x, y, point[0], point[1]))
    t.dot(2)

def determine_point(t, initial_cords):
    '''
    Return the midpoint between the turtles's current coordinates
    and a random one of the of the 3 starting points
    '''

    coord = choice(initial_cords)

    x, y = t.position()

    return [(coord[0] - x) / 2 + x, (coord[1] - y) / 2 + y]

def pythag(a, b, x, y):
    '''
    Do pythagorean theorem to find the length between 2 points
    '''

    return sqrt((x - a) ** 2 + (y - b) ** 2)

screen = Screen()
screen.tracer(False)

turtle = Turtle()
turtle.hideturtle()
turtle.setundobuffer(None)
turtle.radians()
turtle.penup()

fraction_done = 0
curr_time = time()

for iteration in range(iterations):
    # The code will take a while should the triangle be large, so this will give its % completion
    if iteration / iterations > fraction_done:
        screen.update()
        print(fraction_done * 100, r"% done", sep='')
        fraction_done += 0.05
        print(f"Time since last update:\t{time() - curr_time}")
        curr_time = time()

    make_point(turtle, determine_point(turtle, init_c))

screen.update()
screen.exitonclick()

Console

% python3 test.py
0% done
Time since last update: 0.024140119552612305
5.0% done
Time since last update: 1.2522082328796387
10.0% done
Time since last update: 1.619455099105835
15.000000000000002% done
Time since last update: 1.9793877601623535
20.0% done
...
Time since last update: 9.460317373275757
85.00000000000001% done
Time since last update: 10.161489009857178
90.00000000000003% done
Time since last update: 10.585438966751099
95.00000000000003% done
Time since last update: 11.479820966720581