从深度嵌套的 JSON 创建 Pandas DataFrame

声明:本页面是StackOverFlow热门问题的中英对照翻译,遵循CC BY-SA 4.0协议,如果您需要使用它,必须同样遵循CC BY-SA许可,注明原文地址和作者信息,同时你必须将它归于原作者(不是我):StackOverFlow 原文地址: http://stackoverflow.com/questions/21494030/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me): StackOverFlow

提示:将鼠标放在中文语句上可以显示对应的英文。显示中英文
时间:2020-09-13 21:39:01  来源:igfitidea点击:

Create a Pandas DataFrame from deeply nested JSON

pythonjsonpandas

提问by idclark

I'm trying to create a single Pandas DataFrame object from a deeply nested JSON string.

我正在尝试从深度嵌套的 JSON 字符串创建单个 Pandas DataFrame 对象。

The JSON schema is:

JSON 架构是:

{"intervals": [
{
pivots: "Jane Smith",
"series": [
    {
        "interval_id": 0,
        "p_value": 1
       },
     {
         "interval_id": 1,
         "p_value": 1.1162791357932633e-8
     },
   {
        "interval_id": 2,
        "p_value": 0.0000028675012051504467
     }
    ],
   },
  {

"pivots": "Bob Smith",
  "series": [
       {
            "interval_id": 0,
            "p_value": 1
           },
         {
             "interval_id": 1,
            "p_value": 1.1162791357932633e-8
         },
       {
            "interval_id": 2,
            "p_value": 0.0000028675012051504467
         }
       ]
     }
    ]
 }

Desired OutcomeI need to flatten this to produce a table:

期望的结果我需要将其展平以生成表格:

Actor Interval_id Interval_id Interval_id ... 
Jane Smith      1         1.1162        0.00000 ... 
Bob Smith       1         1.1162        0.00000 ... 

The first column is the Pivotsvalues, and the remaining columns are the values of the keys interval_idand p_valuestored in the list series.

第一列是Pivots值,其余列是键的值interval_idp_value存储在列表中series

So far i've got

到目前为止我有

import requests as r
import pandas as pd
actor_data = r.get("url/to/data").json['data']['intervals']
df = pd.DataFrame(actor_data)

actor_datais a list where the length is equal to the number of individuals ie pivots.values(). The df object simply returns

actor_data是一个长度等于个体数量的列表,即pivots.values()。df 对象只是返回

<bound method DataFrame.describe of  pivots             Series
0           Jane Smith  [{u'p_value': 1.0, u'interval_id': 0}, {u'p_va...
1           Bob Smith  [{u'p_value': 1.0, u'interval_id': 0}, {u'p_va...
.
.
.

How can I iterate through that serieslist to get to the dict values and create N distinct columns? Should I try to create a DataFrame for the serieslist, reshape it,and then do a column bind with the actor names?

如何遍历该series列表以获取 dict 值并创建 N 个不同的列?我应该尝试为series列表创建一个 DataFrame,对其进行整形,然后使用演员姓名进行列绑定吗?

UPDATE:

更新:

pvalue_list = [i['p_value'] for i in json_data['series']]

this gives me a list of lists. Now I need to figure out how to add each list as a row in a DataFrame.

这给了我一个列表列表。现在我需要弄清楚如何将每个列表添加为 DataFrame 中的一行。

value_list = []
for i in pvalue_list:
    pvs = [j['p_value'] for j in i]
    value_list = value_list.append(pvs)
return value_list

This returns a NoneType

这将返回一个 NoneType

Solution

解决方案

def get_hypthesis_data():
    raw_data = r.get("/url/to/data").json()['data']
    actor_dict = {}
    for actor_series in raw_data['intervals']:
        actor = actor_series['pivots']
        p_values = []
        for interval in actor_series['series']:
            p_values.append(interval['p_value'])
        actor_dict[actor] = p_values
    return pd.DataFrame(actor_dict).T

This returns the correct DataFrame. I transposed it so the individuals were rows and not columns.

这将返回正确的 DataFrame。我调换了它,所以个人是行而不是列。

采纳答案by Phillip Cloud

I think organizing your data in way that yields repeating column names is only going to create headaches for you later on down the road. A better approach IMHO is to create a column for each of pivots, interval_id, and p_value. This will make extremely easy to query your data after loading it into pandas.

我认为以产生重复列名的方式组织您的数据只会让您以后头疼。更好的方法是恕我直言创造每一个列pivotsinterval_idp_value。在将数据加载到 Pandas 后,这将使查询数据变得非常容易。

Also, your JSON has some errors in it. I ran it through thisto find the errors.

此外,您的 JSON 中有一些错误。我通过来查找错误。

jqhelps here

jq在这里有帮助

import sh
jq = sh.jq.bake('-M')  # disable colorizing
json_data = "from above"
rule = """[{pivots: .intervals[].pivots, 
            interval_id: .intervals[].series[].interval_id,
            p_value: .intervals[].series[].p_value}]"""
out = jq(rule, _in=json_data).stdout
res = pd.DataFrame(json.loads(out))

This will yield output similar to

这将产生类似于

    interval_id       p_value      pivots
32            2  2.867501e-06  Jane Smith
33            2  1.000000e+00  Jane Smith
34            2  1.116279e-08  Jane Smith
35            2  2.867501e-06  Jane Smith
36            0  1.000000e+00   Bob Smith
37            0  1.116279e-08   Bob Smith
38            0  2.867501e-06   Bob Smith
39            0  1.000000e+00   Bob Smith
40            0  1.116279e-08   Bob Smith
41            0  2.867501e-06   Bob Smith
42            1  1.000000e+00   Bob Smith
43            1  1.116279e-08   Bob Smith

Adapted from this comment

改编自此评论

Of course, you can always call res.drop_duplicates()to remove the duplicate rows. This gives

当然,您可以随时调用res.drop_duplicates()以删除重复的行。这给

In [175]: res.drop_duplicates()
Out[175]:
    interval_id       p_value      pivots
0             0  1.000000e+00  Jane Smith
1             0  1.116279e-08  Jane Smith
2             0  2.867501e-06  Jane Smith
6             1  1.000000e+00  Jane Smith
7             1  1.116279e-08  Jane Smith
8             1  2.867501e-06  Jane Smith
12            2  1.000000e+00  Jane Smith
13            2  1.116279e-08  Jane Smith
14            2  2.867501e-06  Jane Smith
36            0  1.000000e+00   Bob Smith
37            0  1.116279e-08   Bob Smith
38            0  2.867501e-06   Bob Smith
42            1  1.000000e+00   Bob Smith
43            1  1.116279e-08   Bob Smith
44            1  2.867501e-06   Bob Smith
48            2  1.000000e+00   Bob Smith
49            2  1.116279e-08   Bob Smith
50            2  2.867501e-06   Bob Smith

[18 rows x 3 columns]