如何将熊猫数据框转换为 Json？答案

【问题标题】：How to convert pandas Data frame into Json?如何将熊猫数据框转换为 Json？
【发布时间】：2023-03-18 11:09:01
【问题描述】：

我正在使用 pandas，并且我在数据框上应用了 groupby。现在我需要将此数据帧转换为 Json 文件。

数据框（名称 = 分组）：

student_id	stuent_name	course_id	subject_name	teacher	weight_score	total_average
1	A	1	Biology	Mr.D	90.1	72.0333
		2	History	Mrs.P	51.8	72.0333
		3	Math	Mrs.C	74.2	72.0333
2	B	1	Biology	Mr.D	50.1	62.1500
		3	Math	Mrs.C	74.2	62.1500
3	C	1	Biology	Mr.D	90.1	72.0333
		2	History	Mrs.P	51.8	72.0333
		3	Math	Mrs.C	74.2	72.0333

数据帧类型：

type(grouped)
pandas.core.frame.DataFrame

当我尝试检索列时，它只允许我获取两列。我想要所有带有列名的值。

grouped.columns
Index(['weighted_score', 'total_average'], dtype='object')

我需要这样的输出：

[{
  "students": [
    {
      "id": 1,
      "name": "A",
      "totalAverage": 72.03,
      "courses": [
        {
          "id": 1,
          "name": "Biology",
          "teacher": "Mr. D",
          "courseAverage": 90.1
        },
        {
          "id": 3,
          "name": "Math",
          "teacher": "Mrs. C",
          "courseAverage": 74.2
        },
        {
          "id": 2,
          "name": "History",
          "teacher": "Mrs. P",
          "courseAverage": 51.8
        }
      ]
    },
    {
      "id": 2,
      "name": "B",
      "totalAverage": 62.15,
      "courses": [
        {
          "id": 1,
          "name": "Biology",
          "teacher": "Mr. D",
          "courseAverage": 50.1
        },
        {
          "id": 3,
          "name": "Math",
          "teacher": "Mrs. C",
          "courseAverage": 74.2
        }
      ]
    },
    {
      "id": 3,
      "name": "C",
      "totalAverage": 72.03,
      "courses": [
        {
          "id": 1,
          "name": "Biology",
          "teacher": "Mr. D",
          "courseAverage": 90.1
        },
        {
          "id": 2,
          "name": "History",
          "teacher": "Mrs. P",
          "courseAverage": 51.8
        },
        {
          "id": 3,
          "name": "Math",
          "teacher": "Mrs. C",
          "courseAverage": 74.2
        }
      ]
    }
  ]
}]

【问题讨论】：

标签： python json pandas pandas-groupby data-analysis

【解决方案1】：

一种方式：

df1 = df.reset_index()
new_dict = (
    df1.set_index(['student_id', 'stuent_name', 'total_average'])
    .apply(dict, 1)
    .groupby(level=[0, 1, 2])
    .agg(list)
    .reset_index(name='courses')
    .to_dict('records')
)

输出：

[{'student_id': 1,
  'stuent_name': 'A',
  'total_average': 72.0333,
  'courses': [{'course_id': '1',
    'subject_name': 'Biology',
    'teacher': 'Mr.D',
    'weight_score': 90.1},
   {'course_id': '1',
    'subject_name': 'History',
    'teacher': 'Mrs.P',
    'weight_score': 51.8},
   {'course_id': '1',
    'subject_name': 'Math',
    'teacher': 'Mrs.C',
    'weight_score': 74.2}]},
 {'student_id': 2,
  'stuent_name': 'B',
  'total_average': 62.15,
  'courses': [{'course_id': '1',
    'subject_name': 'Biology',
    'teacher': 'Mr.D',
    'weight_score': 50.1},
   {'course_id': '1',
    'subject_name': 'Math',
    'teacher': 'Mrs.C',
    'weight_score': 74.2}]},
 {'student_id': 3,
  'stuent_name': 'C',
  'total_average': 72.0333,
  'courses': [{'course_id': '1',
    'subject_name': 'Biology',
    'teacher': 'Mr.D',
    'weight_score': 90.1},
   {'course_id': '1',
    'subject_name': 'History',
    'teacher': 'Mrs.P',
    'weight_score': 51.8},
   {'course_id': '1',
    'subject_name': 'Math',
    'teacher': 'Mrs.C',
    'weight_score': 74.2}]}]

【讨论】：