绘制与掷骰子的次数相对应的海龟直方图答案

【问题标题】：Drawing a turtle histogram that corresponds with the amount of times a dice is rolled绘制与掷骰子的次数相对应的海龟直方图
【发布时间】：2021-03-15 02:20:27
【问题描述】：

我对 python 还很陌生，所以请与我交谈。我正在尝试制作一个海龟直方图，计算各种数字与 100 卷 3 个骰子的次数。但是在用我从掷骰子的试验中得到的总数计算出我的直方图的最大高度之后，直方图的结果与我预期的完全不同。我当前的直方图输出和预期的直方图附在下面。 #请注意，输出会不断变化，因为它有 randrange 提前致谢。

当前代码

from random import randrange
import turtle

totals = dict()
for i in range(3, 19):
    totals[i] = 0
    
# TODO: Set a variable called trials here so we can loop 100 times
trials = 100
for i in range(trials):
     first_roll = randrange(1, 7)
     second_roll = randrange(1, 7)
     third_roll = randrange(1, 7)
     total = first_roll + second_roll + third_roll
     print(total)
     totals[total] += 1


maxheight = 0
for i in range(3, 19):
    print(i, totals[i])
    if totals[i] > maxheight:
        maxheight = totals[i]
scr = turtle.Screen()
t = turtle.Turtle()

t.penup()
t.goto(-138, -175)
t.pendown()

for i in range(3, 19):
    t.write(i, align="center")
    t.forward(20)

t.penup()
t.goto(-150, -175)
t.pendown()

for i in range(3, 19):
    height = int(totals[i] * 300 / maxheight)
    t.forward(height)
    t.right(90)
    t.forward(20)
    t.backward(height)
# TODO: In the end, draw the line at the bottom of our histogram

scr.exitonclick()

电流输出

预期输出

【问题讨论】：

标签： python turtle-graphics python-turtle

【解决方案1】：

你的问题是这段代码：

for i in range(3, 19):
    height = int(totals[i] * 300 / maxheight)
    t.forward(height)
    t.right(90)
    t.forward(20)
    t.backward(height)

它不考虑海龟的当前方向，也不让海龟处于合理的方向。请考虑：

for i in range(3, 19):
    height = int(totals[i] * 300 / maxheight)

    turtle.left(90)
    turtle.forward(height)
    turtle.right(90)
    turtle.forward(20)
    turtle.right(90)
    turtle.forward(height)
    turtle.left(90)

它假设海龟在启动时面向 0 度，而让海龟面向 0 度。包含额外调整的完整代码：

from random import randrange
from turtle import Screen, Turtle

TRIALS = 100
COLUMN_WIDTH = 20

totals = dict()

for i in range(3, 19):
    totals[i] = 0

for _ in range(TRIALS):
    first_roll = randrange(1, 7)
    second_roll = randrange(1, 7)
    third_roll = randrange(1, 7)
    total = first_roll + second_roll + third_roll
    totals[total] += 1

maxheight = 0

for i in range(3, 19):
    if totals[i] > maxheight:
        maxheight = totals[i]

screen = Screen()
turtle = Turtle()

turtle.penup()
turtle.goto(-160 - COLUMN_WIDTH/2, -175)
turtle.pendown()

turtle.forward(COLUMN_WIDTH)

for i in range(3, 19):
    turtle.write(i, align="center")
    turtle.forward(COLUMN_WIDTH)

turtle.penup()
turtle.goto(-160, -175)
turtle.pendown()

for i in range(3, 19):
    height = int(totals[i] * 300 / maxheight)

    turtle.left(90)
    turtle.forward(height)
    turtle.right(90)
    turtle.forward(COLUMN_WIDTH)
    turtle.right(90)
    turtle.forward(height)
    turtle.left(90)

turtle.hideturtle()
screen.exitonclick()

【讨论】：