# -*- coding: gbk -*-
import csv
from matplotlib import pyplot as plt, ticker
from datetime import datetime

from matplotlib.ticker import MultipleLocator

filename = 'changsha天气.csv'

with open(filename) as f:
    reader = csv.reader(f)
    header_row = next(reader)

    #获取每天的最高气温数据
    dates: [datetime] = []
    higts, lows = [], []
    for row in reader:
        try:
            current_date = datetime.strptime(row[0], '%Y-%m-%d')
            higt = int(row[1])
            low = int(row[2])
        except ValueError:
            print(current_date, '缺少信息')
        else:
            dates.append(current_date)
            higts.append(higt)
            lows.append(low)

#根据数据绘制图形,设置窗口大小
fig = plt.figure(dpi=150, figsize=(12, 8))
#plot 拆线图 alpha=(0.1 - 0.9)表示透明度，0为全透明，1为不透明
plt.plot(dates, higts, c='red', alpha=0.5)
plt.plot(dates, lows, c='blue', alpha=0.5)
#填充区间
plt.fill_between(dates, lows, higts, facecolor='black', alpha=0.1)
#设置图形格式
plt.rcParams['font.sans-serif'] = ['SimHei']
plt.title('长沙2023全年气温折线图', fontsize=20, weight='bold', color='blue', fontstyle='italic', loc='center')
plt.xlabel('', fontsize=16)
#日期标签倾斜
fig.autofmt_xdate()
plt.ylabel("温度", fontsize=16, loc='top')
plt.xlabel("年-月", fontsize=16, loc='right')
#设置刻度标记的大小
plt.tick_params(axis='both', which='major',direction='in', pad=3,labelsize=16)


plt.savefig('长沙2023年气温折线图.png')
plt.show()