从深度嵌套的 JSON 创建 Pandas DataFrame
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Create a Pandas DataFrame from deeply nested JSON
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_id并p_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pivots,interval_id和p_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。我通过它来查找错误。
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]

