Question

我正在编写一个Python脚本，我需要按照JSON对象列表中的键进行分组。

我在python中列出了大量JSON对象，格式如下：

[{＆＃39; name＆＃39;：xyz，领土＆＃39;：abc，＆＃39; parameter_a＆＃39;：1，＆＃39; parameter_b＆＃39;：2，＆＃39; parameter_c＆＃39;：3}， ......]

现在我想创建一个标签（比如parameter_d），它应该说出按整数列出的特定区域（Say'abc'）在整个json对象列表中的数量。例如。区域abc在列表中出现3次，因此我希望parameter_d为发生区域abc的不同实例保存值1,2,3。在此先感谢您的帮助。

Answer 1

from json import loads, dumps
from collections import defaultdict

json_string = """
[
    {"name": "xyz", "territory": "abc", "parameter_a": 1, "parameter_b": 2, "parameter_c": 3},
    {"name": "qrs", "territory": "def", "parameter_a": 1, "parameter_b": 2, "parameter_c": 3},
    {"name": "tuv", "territory": "abc", "parameter_a": 1, "parameter_b": 2, "parameter_c": 3},
    {"name": "abc", "territory": "abc", "parameter_a": 1, "parameter_b": 2, "parameter_c": 3}
]"""

# Step 1: convert from JSON to Python:
python_object = loads(json_string)

# Step 2: Add `parameter_d` to each item in list,
# using defaultdict(int) as a counter:
counts = defaultdict(int)
for item in python_object:
    counts[item["territory"]] += 1
    item["parameter_d"] = counts[item["territory"]]

# Step 3: convert from Python to JSON
json_string = dumps(python_object, indent=2)
print json_string

Answer 2

使用Rob的这部分答案进行设置：

from json import loads, dumps
from collectins import defaultdict

json_string = """
[
    {"name": "xyz", "territory": "abc", "parameter_a": 1, "parameter_b": 2, "parameter_c": 3},
    {"name": "qrs", "territory": "def", "parameter_a": 1, "parameter_b": 2, "parameter_c": 3},
    {"name": "tuv", "territory": "abc", "parameter_a": 1, "parameter_b": 2, "parameter_c": 3},
    {"name": "abc", "territory": "abc", "parameter_a": 1, "parameter_b": 2, "parameter_c": 3}
]"""

# Step 1: convert from JSON to Python:
python_object = loads(json_string)

您可以创建地区字典，然后更新您的对象：

territories = defaultdict(list)

for i, item in enumerate(python_object):
    territories[item['territory']].append(i)

for item in python_object:
    item['parameter_d'] = territories[item['territory']]

print(dumps(python_object, indent=2))

如何通过操作python中的json对象列表来进行组操作？

2 个答案: