第六课--json数据的使用和分析

import json
import pygal
import math
from itertools import groupby

# 提取json数据
filename = 'btc_close_2017.json'

with open(filename) as f:
    btc_data = json.load(f)
dates = []
months = []
weeks = []
weekdays = []
closes = []
for btc_dict in btc_data:
    try:
        date = btc_dict['date']
        month = int(btc_dict['month'])
        week = int(btc_dict['week'])
        weekday = btc_dict['weekday']
        close = int(float(btc_dict['close']))  # python不能把小数字符串直接转成int
    except ValueError as e:
        print(e)
    else:
        dates.append(date)
        months.append(month)
        weeks.append(week)
        weekdays.append(weekday)
        closes.append(close)
        # print("{} is month {} week {} , {} , the close price is {} RMB".format(date,month,week,weekday,close))
# 使用pygal画折线图
line_chart = pygal.Line(x_label_rotation=20,
                        show_minor_x_labels=False)  # x_label_rotation让X轴上的数据顺时针旋转20°，show_minor_x_labels不用显示所有的X轴标签
line_chart.title = '收盘价'
line_chart.x_labels = dates
N = 20
line_chart.x_labels_major = dates[::N]  # X轴坐标每隔20天显示一次
# line_chart.add('收盘价', closes)
# line_chart.render_to_file('收盘价折线图.svg')
# 时间序列特征（使用math函数的对数）
close_log = [math.log10(x) for x in closes]
line_chart.add('log收盘价', close_log)
line_chart.render_to_file('收盘价对数变换折线图（￥）.svg')


def draw_line(x_data, y_data, title, y_legend):
    xy_map = []
    for x, y in groupby(sorted(zip(x_data, y_data)), key=lambda _: _[0]):
        y_list = [v for _, v in y]
        xy_map.append([x, sum(y_list) / len(y_list)])
    x_unique, y_mean = [*zip(*xy_map)]
    line_chart = pygal.Line()
    line_chart.title = title
    line_chart.x_labels = x_unique
    line_chart.add(y_legend, y_mean)
    line_chart.render_to_file(title + '.svg')
    return line_chart


idx_month = dates.index('2017-12-01')
draw_line(months[:idx_month], closes[:idx_month], '收盘价月日均值（￥）', '月日均值')
idx_week = dates.index('2017-12-11')
draw_line(weeks[1:idx_week], closes[1:idx_week], '收盘价周日均值（￥）', '周日均值')

idx_week = dates.index('2017-12-11')
wd = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday']
weekdays_int = [wd.index(w) + 1 for w in weekdays[1:idx_week]]
line_chart_weekday = draw_line(weekdays_int, closes[1:idx_week], '收盘价星期均值（￥）', '星期均值')
line_chart_weekday.x_labels = ['周一', '周二', '周三', '周四', '周五', '周六', '周日']
line_chart_weekday.render_to_file('收盘价星期均值（￥）.svg')

with open('收盘价Dashboard.html', 'w', encoding='utf8') as html_file:
    html_file.write('收盘价\n')
    for svg in ['die_visual.svg', 'die_visuals.svg', '收盘价周日均值（￥）.svg', '收盘价对数变换折线图（￥）.svg', '收盘价折线图.svg',
                '收盘价星期均值（￥）.svg', '收盘价月日均值（￥）.svg']:
        html_file.write('\n'.format(svg))
    html_file.write('')