使用另一个列表的元素创建空列表

Question

我有一份年份清单：years = ["2020", "2019", "2018", "2017", "2016", "2015", "2014", "2013"]以及我想从网络抓取中获取的信息列表：info = ["played_games", "games_won", "efectivity", "championship_won", "finals", "semi-finals", "quarterfinals"]我需要迭代多年，这样我就可以用信息中元素的名称+相应的年份来制作空列表，这样我就可以稍后附加信息，即：played_games2020 = []games_won2020 = []efectivity2020 = []etcplayed_games2019 = []games_won2019 = []efectivity2019 = []etc任何帮助将非常感激！问候

Answer 1

编辑：

我相信更快的解决方案是使用dict comprehensionwith itertools.product。解决方案只是一行代码：

import itertools

example_dict = {x:[] for x in [x[0]+x[1] for x in itertools.product(info,years)]}

输出与以下解决方案相同。

正如 han solo 在他们的评论中所建议的那样，这似乎更合适defaultdict(list)。基本上解决方案是：

from collections import defaultdict

example_dict = defaultdict(list)

for i in years:

   for j in info:

       example_dict[j+i]

print(example_dict)

输出：

defaultdict(list,

            {'championship_won2013': [],

             'championship_won2014': [],

             'championship_won2015': [],

             ...

             'semi-finals2018': [],

             'semi-finals2019': [],

             'semi-finals2020': []})

Answer 2

您可以使用一维字典并在一个字符串中合并 itme 和不好的年份，您宁愿使用二维字典并首先填充空列表，然后通过两个信息访问：项目+日期

一个项目然后一年

values = {i: {year: [] for year in years} for i in info}

{'played_games': {'2020': [], '2019': [], '2018': [], '2017': [], '2016': [], '2015': [], '2014': [], '2013': []}, 

 'games_won':    {'2020': [], '2019': [], '2018': [], '2017': [], '2016': [], '2015': [], '2014': [], '2013': []}, 

 'efectivity':   {'2020': [], '2019': [], '2018': [], '2017': [], '2016': [], '2015': [], '2014': [], '2013': []}, 

  ...}

# add data like

values["played_games"]['2014'].append("foo")

一年然后一个项目

values = {year: {i: [] for i in info} for year in years}

{'2020': {'played_games': [], 'games_won': [], 'efectivity': [], 'championship_won': [], 'finals': [], 'semi-finals': [], 'quarterfinals': []}, 

 '2019': {'played_games': [], 'games_won': [], 'efectivity': [], 'championship_won': [], 'finals': [], 'semi-finals': [], 'quarterfinals': []}, 

 '2018': {'played_games': [], 'games_won': [], 'efectivity': [], 'championship_won': [], 'finals': [], 'semi-finals': [], 'quarterfinals': []}, 

  ...}

# add data like

values['2014']["played_games"].append("foo")

Answer 3

您可以创建一个包含 n 个空列表的列表。与n = len(info) * len(years)。其中 pos 0 的列表是 (info[0],years[0]) ，1 的列表是 (info[0],years[1])....

如果需要，您还可以将名称存储在字符串列表中，具有相同的原理（信息和年份的双循环）。

Answer 4

使用 2 个循环，你可以试试这个：

years = ["2020", "2019", "2018", "2017", "2016", "2015", "2014", "2013"]

info = ["played_games", "games_won", "efectivity", "championship_won", "finals", "semi-finals", "quarterfinals"]

all_arrays_dict = {}

for x in years:

  for y in info:

    all_arrays_dict[y+x] = []

print(all_arrays_dict)

这是输出字典：

{

  "played_games2020": [],

  "games_won2020": [],

  "efectivity2020": [],

  "championship_won2020": [],

  "finals2020": [],

  "semi-finals2020": [],

  "quarterfinals2020": [],

  "played_games2019": [],

  "games_won2019": [],

  .

  .

  .

}