生成数据并可视化 

from random import randint
import pygal

class Die():
    def __init__(self,num_sides=6):
        self.num_sides = num_sides

    def roll(self):
        #随机返回一个1到num_sides之间的数
        return randint(1, self.num_sides)

die = Die()
results = []
for roll in range(100):
    result = die.roll()
    results.append(result)

print(results)

#分析结果
frequencies = []
for values in range(1, die.num_sides+1):
    frequency = results.count(values)
    frequencies.append(frequency)
print(frequencies)

"""绘制直方图"""
#对数据进行可视化
hist = pygal.Bar()
hist.title = "随机数统计"
hist.x_labels = ['1', '2', '3', '4', '5', '6']
hist.x_title = "Result"
hist.y_title = "统计结果"

hist.add('D6', frequencies)
hist.render_to_file('die_visual.svg')

访问http://www.pygal.org  单击Documentation，再单击Chart types。每个示例包含源码。

摘自Python编程从入门到实践304~307页