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python - 根据 JSON 文件中的特定参数制作元素列表

问题描述

我正在为学校做作业，我被要求列出特定年份和类别的诺贝尔和平奖获得者的名单。这是 JSON 文件的示例：

[{
        'year': '2018',
        'category': 'physics',
        'overallMotivation': '“for       groundbreaking inventions in the field of laser physics”',
        'laureates': [{
                'id': '960',
                'firstname': 'Arthur',
                'surname': 'Ashkin',
                'motivation': '"for the optical tweezers and their application to biological systems"',
                'share': '2'
            }, {
                'id': '961',
                'firstname': 'Gérard',
                'surname': 'Mourou',
                'motivation': '"for their method of generating high-intensity, ultra-short optical pulses"',
                'share': '4'
            }, {
                'id': '962',
                'firstname': 'Donna',
                'surname': 'Strickland',
                'motivation': '"for their method of generating high-intensity, ultra-short optical pulses"',
                'share': '4'
            }
        ]
    }, {
        'year': '2018',
        'category': 'chemistry',
        'laureates': [{
                'id': '963',
                'firstname': 'Frances H.',
                'surname': 'Arnold',
                'motivation': '"for the directed evolution of enzymes"',
                'share': '2'
            }, {
                'id': '964',
                'firstname': 'George P.',
                'surname': 'Smith',
                'motivation': '"for the phage display of peptides and antibodies"',
                'share': '4'
            }, {
                'id': '965',
                'firstname': 'Sir Gregory P.',
                'surname': 'Winter',
                'motivation': '"for the phage display of peptides and antibodies"',
                'share': '4'
            }
        ]
    }
]

我应该找到一种方法来找到赢得特定类别和年份的人的全名，这是我当前的代码

def get_laureates(dict_prizes, year = "none", category = "none"):


    names = []
    for row in dict_prizes: 
        if row["category"] == category:
            names.append(row["firstname"] + row['surname'])
    return names

year = 2018
category = "peace"

get_laureates(dict_prizes, year = 2018, category = "peace")

这是输出

    TypeError                                 Traceback (most recent call last)
<ipython-input-168-57a2293c1bca> in <module>
         11 category = "peace"
         12 # test your function here
    ---> 13 get_laureates(dict_prizes, category = "peace")

    <ipython-input-168-57a2293c1bca> in get_laureates(dict_prizes, year,         category)
          4     names = []
          5     for row in dict_prizes:
    ----> 6         if row["category"] == category and row["year"] == year:
          7             names.append(row["firstname"] + row['surname'])
          8     return names

    TypeError: string indices must be integers

我知道这段代码中有很多错误，我无法将年份转换为整数，即使删除了“years”参数，我也无法仅使用类别生成结果。任何帮助都将不胜感激，因为我对 JSON 完全一无所知（给我的阅读材料实际上只是教会了我转储和加载）。

标签： pythonpython-3.x

解决方案

在这里，我刚刚通过使用解决了您的功能，如果它检查两者year并category匹配您提供的输入。这样您就可以搜索属于该特定条件的所有值。此外，在检查条件时year需要将其视为字符串，因为它在 json 文件中是如何表达的。您显然可以删除else:仅用于验证目的的行。

def get_laureates(category,year,json):  
    names = []
    for j in range(len(json)):
        if (json[j]['year'] == str(year)) and (json[j]['category'] == category):
            for i in range(len(json[j]['laureates'])):
                names.append(json[j]['laureates'][i]['firstname'] + ' ' + json[j]['laureates'][i]['surname'])
        else:
            print('Not found for category '+category+' and year '+str(year))
    return names
print(get_laureates(category='physics',year=2018,json=json))

输出：

Not found for category physics and year 2018
['Arthur Ashkin', 'Gérard Mourou', 'Donna Strickland']

超级检查一致性

您可以在定义函数后立即添加：

possibilities = ['physics','chemistry']
for i in range(len(possibilities)):
    print(get_laureates(category=possibilities[i],year=2018,json=json))

输出：

Not found for category physics and year 2018
['Arthur Ashkin', 'Gérard Mourou', 'Donna Strickland']
Not found for category chemistry and year 2018
['Frances H. Arnold', 'George P. Smith', 'Sir Gregory P. Winter']

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