Python 中使用 turtle 的饼图的每个部分的不同颜色

Question

import turtle

from turtle import *
##lets draw a pie chart first
##segment_labels = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"]

segment_labels= ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']
prob_of_letter= [10.52,1.94,6.91,6.83,22.65,9.42,4.10,4.68,11.92,.56,1.20,10.80,3.29,11.33,12.95,5.83,.01,11.14,14.11,14.69,4.05,1.93,2.96,2.78,3.02,.16] ##we  can get these number from the frequency coding part. 
colors=['yellow','green','red','black','yellow','blue','red','white','yellow',
    'green','red','black','yellow','blue','red','white','yellow','green','red','bla    ck','yellow','blue','red','white','red','mediumpurple']
radius = 100 ## circumference of a circle = 2pie*r
penup()
forward(radius)
left(90)
pendown()
color('gray')
begin_fill()
circle(radius)
end_fill()
home()
right(90)
color('darkblue')

def letter(prob_of_letter):
    perc=0
    radius =100
    for percent in prob_of_letter:
        letter = percent * 360
        perc += letter
        setheading(perc)
        pendown()
        forward(radius)
        penup()
        home()
letter(prob_of_letter)

如何为 .txt 文件中最常出现的字母绘制饼图？

Answer 1

在我们讨论代码之前，让我们讨论一下数据。我理解将颜色分配分开是因为它们是任意的，但是字母和频率紧密地联系在一起，所以它们的数据结构应该反映这一点——而不是单独的列表，我把它们做成一个元组列表：

letter_frequencies = [('a', 10.52), ('b', 1.94), ('c', 6.91), ('d', 6.83), ...]

您的频率加起来不等于 100 或任何接近的值，因此它们不是变量名称所暗示的百分比。为了解决这个问题，我们将它们加起来并将它们视为总数的一小部分。证实了我对注释的普遍看法，你单独的代码注释对这个问题的实现没有价值：

radius = 100 ## circumference of a circle = 2pie*r

下面，我将问题分为两步：首先，按照频率按比例绘制颜色切片；其次，在图表外侧写上字母标签。一些字母频率非常小，以至于它们在饼图上只显示为一条线，因此我们无法在图表内进行标记。增加饼图的半径会有一点帮助。

绘制饼图的关键在于使用海龟circle()函数的extent参数来绘制一个合适大小的圆弧。然后我们将该弧线连接到圆心以制作切片。

''' Let's draw a pie chart '''

from turtle import Turtle, Screen
from itertools import cycle

letter_frequencies = [ \
    ('a', 10.52), ('b', 1.94), ('c', 6.91), ('d', 6.83), ('e', 22.65), \
    ('f', 9.42), ('g', 4.1), ('h', 4.68), ('i', 11.92), ('j', 0.56), \
    ('k', 1.2), ('l', 10.8), ('m', 3.29), ('n', 11.33), ('o', 12.95), \
    ('p', 5.83), ('q', 0.01), ('r', 11.14), ('s', 14.11), ('t', 14.69), \
    ('u', 4.05), ('v', 1.93), ('w', 2.96), ('x', 2.78), ('y', 3.02), ('z', 0.16)]

COLORS = cycle(['yellow', 'green', 'red', 'cyan', 'white', 'blue', 'mediumpurple'])

RADIUS = 175
LABEL_RADIUS = RADIUS * 1.33
FONTSIZE = 18
FONT = ("Ariel", FONTSIZE, "bold")

# The pie slices

total = sum(fraction for _, fraction in letter_frequencies)  # data doesn't sum to 100 so adjust

baker = Turtle()  # because we're baking a pie
baker.penup()
baker.sety(-RADIUS)
baker.pendown()

for _, fraction in letter_frequencies:
    baker.fillcolor(next(COLORS))
    baker.begin_fill()
    baker.circle(RADIUS, fraction * 360 / total)
    position = baker.position()
    baker.goto(0, 0)
    baker.end_fill()
    baker.setposition(position)

# The labels

baker.penup()
baker.sety(-LABEL_RADIUS)

for label, fraction in letter_frequencies:
    baker.circle(LABEL_RADIUS, fraction * 360 / total / 2)
    baker.write(label, align="center", font=FONT)
    baker.circle(LABEL_RADIUS, fraction * 360 / total / 2)

baker.hideturtle()

screen = Screen()
screen.exitonclick()

这会生成一个粗略的饼图，您需要根据自己的特定需求对其进行微调：

Python 中使用 turtle 的饼图的每个部分的不同颜色

Different color for each segment of a pie chart using turtle in Python

python

turtle-graphics

python-3.5