Python制作折线图

1 #!usr/bin/env python3
2 # -*-coding=utf-8 -*-
3 '''
4 制作一个简单的交易走势图。源码大部分来自<python编程从入门到实践>
5 过程分析:
6 1,从网站下载数据并存储到本地，两种方法:
7 a,urlopen
8 b,requests
9 2,读取本地数据，利用pygal制作交易走势图
10 '''
11 #正文开始
12 from __future__ import (absolute_import, division, print_function, unicode_literals)
13 try:
14 from urllib2 import urlopen
15 except ImportError:
16 from urllib.request import urlopen
17 import json
18 import requests
19 import pygal
20 from pygal.style import LightColorizedStyle as LCS,LightenStyle as LS
21
22 #第一种方法利用urlopen提取网络上存储的数据
23 #定义要提取数据的url
24 URL = "https://www.xxx.com/btc_close_2017.json"
25 read_url = urlopen(URL) #读取URL
26 read_response = read_url.read() #读取返回的数据
27
28 #开始存储数据到本地, 以'wb'形式(二进制)
29 with open('btc_close_2017_urllib.json', 'wb') as file_object:
30 file_object.write(read_response) #将读取到的数据写入到文件
31
32 file_urllib = json.loads(read_response)
33 print(file_urllib)
34
35 #第二种方法利用requests提取网络上存储的数据
36 #定义要提取数据的URL
37 URL = "https://www.xxx.com/btc_close_2017.json"
38 response = requests.get(URL) #利用requests读取URL并获取数据
39
40 #开始存储数据到本地文件;
41 with open('btc_close_2017_requests.json', 'w') as file_object:
42 file_object.write(response.text) #写入数据到本地文件，要以str格式写入
43
44 file_requests = response.json()
45 print(file_requests)
46
47 print("-----------------------I am delimiter-----------------")
48 #打印一下两种方法是不是获取到相同的数据
49 print(file_urllib == file_requests) #True
50
51 #开始读取相关数据
52 filename = 'btc_close_2017.json'; #加载文件
53
54 #以读的方式打开文件
55 with open(filename) as file_object:
56 btc_data = json.load(file_object) #将读取到的数据加载为json格式
57
58 print(btc_data) #打印是否符合预期
59
60 #打印每一天的信息,并将字符串转换成数值型的:
61 for btc_dict in btc_data:
62 date = btc_dict['date']
63 month = int(btc_dict['month'])
64 week = int(btc_dict['week'])
65 weekday = btc_dict['weekday']
66 close_price = int(float(btc_dict['close'])) #先将字符串转换为浮点型,再将浮点型转换成整型
67 print("{} is month: {}, week: {}, weekday: {}, the close price is: {}".format(date,month,week,weekday,close_price))
68
69
70 #可视化,开始绘制收盘价折线图
71
72 #定义空列表以存储循环得到的项
73 dates, months, weeks, weekdays, close_prices = [], [], [], [], []
74 #循环读取btc_data里的每一项
75 for btc_dict in btc_data:
76 date = btc_dict['date']
77 month = int(btc_dict['month'])
78 week = int(btc_dict['week'])
79 weekday = btc_dict['weekday']
80 close_price = int(float(btc_dict['close'])) #先将字符串转换为浮点型,再将浮点型转换成整型
81
82 #将每一项追加到对应的空列表
83 dates.append(date)
84 months.append(month)
85 weeks.append(week)
86 weekdays.append(weekday)
87 close_prices.append(close_price)
88
89 line_chart = pygal.Line(x_label_rotation=20,show_minor_x_labels=False) #x轴标签顺时针旋转20度,show_minor_x_labels告诉pygal不必显示全部的x轴标签
90 line_chart.title = "Close Price ($)" #标题
91 line_chart.x_title = "Dates" #x轴标题
92 line_chart.y_title = "Price" #y轴标题
93 line_chart.x_labels = dates #x轴标签
94 line_chart.x_labels_major = dates[::20] #让x轴坐标每隔20天显示第一次;
95 line_chart.add("BTC", close_prices) #
96 line_chart.render_to_file('closeprice.svg')
97
98 '''
99 写一些折线图的样式
100 '''
101 my_style = LS("#999888",base_style=LCS)
102 my_config = pygal.Config()
103 my_config.x_label_rotation = 20
104 my_config.show_legend = False
105 my_config.show_minor_x_labels = False
106 my_config.title_font_size = 10
107 my_config.label_font_size = 10
108 my_config.major_label_font_size = 18
109 my_config.truncate_label = 10
110 my_config.show_y_guides = False
111 my_config.width = 1000
112
113 #利用样式可视化
114 line_chart = pygal.Line(my_config,style=my_style)
115 line_chart.title = "BTC close price in 2017"
116 line_chart.x_title = "Dates"
117 line_chart.y_title = "Price"
118 line_chart.x_labels = dates
119 line_chart.x_labels_major = dates[::20]
120 line_chart.add("SPJ",close_prices)
121 line_chart.render_to_file("closeprice1.svg")