Python3 高效处理 JSON 与 CSV 数据：读取、提取与可视化

'''
The i18n module was removed in pygal-2.0.0.
however, it can now be found in the pygal_maps_world plugin.
You can install that with pip install pygal_maps_world.
Then you can access COUNTRIES as pygal.maps.world.COUNTRIES:
from pygal.maps.world import COUNTRIES
Whats left of the i18n module can be imported with:
from pygal_maps_world import i18n
'''
#获取两个字母的国别码
from pygal_maps_world.i18n import COUNTRIES
def get_country_code(country_name):
    for code,name in COUNTRIES.items():
        if name==country_name:
            return code
        return None

import json
from Country_codes import get_country_code

# 提取相关数据
filename = 'population_data.json'
with open(filename, encoding='utf-8') as f:
    pop_data = json.load(f)
    
    for pop_dict in pop_data:
        # 获得每个国家2010年的人口数量
        if pop_dict['Year'] == '2010':
            country_name = pop_dict['Country Name']
            population = int(float(pop_dict['Value']))  # 先转浮点后转整数，防科学计数法残留
            code = get_country_code(country_name)
            if code:
                print(f'{code}:{population}')
            else:
                print(f'ERROR-{country_name}')

import csv
from matplotlib import pyplot as plt
from datetime import datetime

# 读取CSV文件数据
filename = 'sitka_weather_2014.csv'
with open(filename, encoding='utf-8') as f:
    reader = csv.reader(f)
    header_row = next(reader)
    dates, highs, lows = [], [], []
    
    for row in reader:
        current_date = datetime.strptime(row[0], '%Y-%m-%d')
        dates.append(current_date)
        highs.append(int(row[1]))
        lows.append(int(row[3]))

# 根据数据绘制图形
fig = plt.figure(dpi=128, figsize=(10, 6))
plt.plot(dates, highs, c='red', alpha=0.5)
plt.plot(dates, lows, c='blue', alpha=0.5)
plt.fill_between(dates, highs, lows, facecolor='blue', alpha=0.1)
plt.title('Daily High and Low Temperature - 2014', fontsize=24)
plt.xlabel('', fontsize=16)
plt.ylabel('Temperature (°F)', fontsize=16)
plt.tick_params(axis='both', which='major', labelsize=16)
fig.autofmt_xdate()
plt.show()

import json

f = open("D:/文件/资料/GT.csv", "r", encoding='utf-8')
data_lines = f.readlines()
f.close()
data_lines.pop(0)  # 剔除表头行

values = []
for line in data_lines:
    line = line.replace("\n", "")
    values.append(line.split(","))

# 请根据实际数据列名替换下方 keys 列表，保持顺序一致
keys = ["stamp_sec", "obj_stamp_sec", "frame_num", "source", "id", "track_id",
        "lane_id", "center_x", "center_y", "center_z", "closest_point_x",
        "closest_point_y", "closest_point_z", "velocity_x", "velocity_y",
        "type", "is_tracked", "height", "length", "width"]

# 构建字典列表并导出
fw = open("output_data.json", "w", encoding='utf-8')
dict_re = [dict(zip(keys, row)) for row in values] if values else None
a = json.dumps(dict_re, indent=4, ensure_ascii=False)
fw.write(a)
fw.close()
print("CSV已成功转换为JSON格式。")