搜索字典的值，如果值在里面则输出嵌套字典

Question

我碰壁了

我需要搜索特定值并输出该值所在的整个字典：

这是我的原始词典：

dictionary1={ "Perth":{"Division": "Perth","Staff number":10,"Year formed":1995},"Darwin":{"Division": "Darwin","Staff number":5,"Year formed":2000},"Brisbane":{"Division": "Brisbane","Staff number":15,"Year formed":1995}}

使用参数 1995year_formed_data(1995) 调用函数后，输出应为：

{1995:[{"Division": "Perth","Staff number":10,"Year formed":1995},{"Division": "Brisbane","Staff number":15,"Year formed":1995}]}

同样如果：

year_formed_data(2000)

{2000:[{"Division": "Darwin","Staff number":5,"Year formed":2000}]}

这是我的代码：

def year_formed_data(yr):
    year={}
    for business,data in dictionary1.items():
        if data ==yr:
            year[yr]={list({"Division": ,"Staff number": ,"Year formed": }
    print(year)
year_formed_data(1995)

再次感谢！

Answer 1

你也许可以利用 collections.<b>defaultdict</b>:

from collections import defaultdict

DATA = {
    'Perth': {'Division': 'Perth', 'Staff number': 10, 'Year formed': 1995},
    'Darwin': {'Division': 'Darwin', 'Staff number': 5, 'Year formed': 2000},
    'Brisbane': {'Division': 'Brisbane', 'Staff number': 15, 'Year formed': 1995},
}

def year_formed_data(yr: int) -> dict:
    year_data = defaultdict(list)
    for city, data in DATA.items():
        if data['Year formed'] == yr:
            year_data[yr].append(data)
    return dict(year_data)

def main() -> None:
    print(f'{year_formed_data(1995) = }')
    print(f'{year_formed_data(2000) = }')
    print(f'{year_formed_data(2005) = }')

if __name__ == '__main__':
    main()

输出：

year_formed_data(1995) = {1995: [{'Division': 'Perth', 'Staff number': 10, 'Year formed': 1995}, {'Division': 'Brisbane', 'Staff number': 15, 'Year formed': 1995}]}
year_formed_data(2000) = {2000: [{'Division': 'Darwin', 'Staff number': 5, 'Year formed': 2000}]}
year_formed_data(2005) = {}

Answer 2

以下是您的操作方法。您可以查看注释行以了解您的错误。 :

dictionary1={ "Perth":{"Division": "Perth","Staff number":10,"Year formed":1995},"Darwin":{"Division": "Darwin","Staff number":5,"Year formed":2000},"Brisbane":{"Division": "Brisbane","Staff number":15,"Year formed":1995}}

def year_formed_data(yr):
    year={}
    year[yr] = [] # Create a list for that particular year to store required data.
    for business, data in dictionary1.items():
        # data was in the form of a dictionary. You are required to extract `Year formed` from that.  
        if (data['Year formed'] == yr):
            # Append the Division, Staff, Year formed if yr matches.
            year[yr].append({"Division": data['Division'] ,"Staff number":  data['Staff number'], "Year formed":  data['Year formed']})

    print(year)
year_formed_data(1995)

输出：

{1995: [{'Division': 'Perth', 'Staff number': 10, 'Year formed': 1995}, {'Division': 'Brisbane', 'Staff number': 15, 'Year formed': 1995}]}

搜索字典的值，如果值在里面则输出嵌套字典

Search value for dictionary and output the nested dictionary if the value is inside

python

dictionary

function

list