Question

我正在尝试使用以下代码选择随机国家/地区的随机城市：

COUNTRIES= ["NL", "NO"]

NL = [
    "Assen", "Almere", "Leeuwarden", "Nijmegen", "Groningen", 
    "Maastricht", "Eindhoven", "Amsterdam", "Enschede", "Utrecht", 
    "Middelburg", "Rotterdam"
]

NO = [
    "Fredrikstad", "Baerum", "Oslo", "Ringsaker", "Gjovik", 
    "Drammen", "Sandefjord", "Skien", "Arendal", "Kristiansand", 
    "Stavanger", "Bergen", "Forde", "Alesund", "Trondheim", 
    "Stjordal", "Bodo", "Tromso", "Alta"
]

CHOSEN_CITY = random.choice(random.choice(COUNTRIES))

print CHOSEN_CITY

但是，这只能给我一个'L'，'O'或N。我在这里做错了什么？

Answer 1

试试这个

random.choice(NL + NO)

Answer 2

您选择的是一个随机国家/地区，然后从每个字符串中选择一个随机字母。这不是Python的工作原理。

更好的设置是将数据存储在字典中，如下所示。然后，您可以选择一个随机国家（通过在dict中选择一个随机键）。然后，您将使用该随机密钥选择随机城市。

import random

data = {
    'NL': ["Assen", "Almere", "Leeuwarden", "Nijmegen", "Groningen", "Maastricht", 
           "Eindhoven", "Amsterdam", "Enschede", "Utrecht", "Middelburg", "Rotterdam"],
    'NO': ["Fredrikstad", "Baerum", "Oslo", "Ringsaker", "Gjovik", "Drammen",
           "Sandefjord", "Skien", "Arendal", "Kristiansand", "Stavanger", "Bergen", 
           "Forde", "Alesund", "Trondheim", "Stjordal", "Bodo", "Tromso", "Alta"]
}

random_country = random.choice(list(data.keys()))
random_city = random.choice(data[random_country])

print(random_country, random_city)
# NO Drammen

Answer 3

这不是Python的工作方式！一个列表中的字符串不是对另一个变量的引用，即使它们共享相同的名称。

NL = ["Assen", "Almere", "Leeuwarden"]  # truncated for clarity
NO = ["Fredrikstad", "Baerum", "Oslo"]

countries = [NL, NO]  # refer to variables, not just strings
chosen_city = random.choice(random.choice(countries))

print(chosen_city)

应该有效。只需从两个附加列表中选择就更清楚了，但在您的特定情况下可能无效。

根据第三个列表中的随机项，从两个列表中选择一个随机项

3 个答案: