我的四个字段，分别为年份，电影编号，电影名字，评价平均分，现在我有一个需求，按照年份进行分组。计算每部电影的平均评分，平均评分保留小数点后一位，并按评分大小进行排序，评分一样，按照电影名排序。相同年份的输出到一个文件中

好的，这是一个数据处理的任务。您可以使用Python来完成这个任务。首先，您需要读取包含电影数据的文件。假设数据保存在一个名为“movies.csv”的CSV文件中，您可以使用以下代码读取它：

import csv

# 读取CSV文件
with open('movies.csv', newline='', encoding='utf-8') as csvfile:
    reader = csv.reader(csvfile)
    # 跳过标题行
    next(reader)
    # 遍历每一行数据
    for row in reader:
        # 处理数据
        pass

然后，您需要将电影数据按照年份进行分组，并计算每部电影的平均评分。您可以使用Python的字典来实现这个功能。代码可能如下所示：

import csv

# 读取CSV文件
with open('movies.csv', newline='', encoding='utf-8') as csvfile:
    reader = csv.reader(csvfile)
    # 跳过标题行
    next(reader)

    # 创建一个字典来保存每个年份的电影数据
    movies_by_year = {}

    # 遍历每一行数据
    for row in reader:
        # 解析数据
        year = int(row[0])
        movie_id = int(row[1])
        movie_name = row[2]
        rating = float(row[3])

        # 将电影数据按照年份进行分组
        if year not in movies_by_year:
            movies_by_year[year] = {}

        # 计算每部电影的平均评分
        if movie_id not in movies_by_year[year]:
            movies_by_year[year][movie_id] = {'name': movie_name, 'ratings': [rating]}
        else:
            movies_by_year[year][movie_id]['ratings'].append(rating)

    # 遍历每个年份的电影数据
    for year in movies_by_year:
        # 计算每部电影的平均评分
        for movie_id in movies_by_year[year]:
            ratings = movies_by_year[year][movie_id]['ratings']
            avg_rating = round(sum(ratings) / len(ratings), 1)
            movies_by_year[year][movie_id]['avg_rating'] = avg_rating

最后，您需要将结果按照评分大小进行排序，并输出到文件中。您可以使用Python的sorted()函数来排序，代码可能如下所示：

import csv

# 读取CSV文件
with open('movies.csv', newline='', encoding='utf-8') as csvfile:
    reader = csv.reader(csvfile)
    # 跳过标题行
    next(reader)

    # 创建一个字典来保存每个年份的电影数据
    movies_by_year = {}

    # 遍历每一行数据
    for row in reader:
        # 解析数据
        year = int(row[0])
        movie_id = int(row[1])
        movie_name = row[2]
        rating = float(row[3])

        # 将电影数据按照年份进行分组
        if year not in movies_by_year:
            movies_by_year[year] = {}

        # 计算每部电影的平均评分
        if movie_id not in movies_by_year[year]:
            movies_by_year[year][movie_id] = {'name': movie_name, 'ratings': [rating]}
        else:
            movies_by_year[year][movie_id]['ratings'].append(rating)

    # 遍历每个年份的电影数据
    for year in movies_by_year:
        # 计算每部电影的平均评分
        for movie_id in movies_by_year[year]:
            ratings = movies_by_year[year][movie_id]['ratings']
            avg_rating = round(sum(ratings) / len(ratings), 1)
            movies_by_year[year][movie_id]['avg_rating'] = avg_rating

        # 按照评分大小进行排序
        sorted_movies = sorted(movies_by_year[year].values(), key=lambda x: (-x['avg_rating'], x['name']))

        # 输出到文件中
        with open(f'{year}.txt', 'w', encoding='utf-8') as outfile:
            for movie in sorted_movies:
                outfile.write(f"{movie['name']},{movie['avg_rating']}\n")

这段代码将结果按照年份写入不同的文本文件中，文件名为年份，文件内容为每部电影的名字和平均评分，按照评分大小进行排序。