我有以下 JSON 字典。 我想做的是删除所有“close_approach_data”对象,其中“orbiting_body”不是“地球”。 问题是可能有不止一个具有 Orbiting_body:“Earth”的物体,并且在所有这些物体之间,我尝试保留具有最小“approach_date”的物体。
data = [
{
"id": "01",
"close_approach_data": [
{
"orbiting_body": "Earth",
"approach_date": "1945-06-07"
},
{
"orbiting_body": "Earth",
"approach_date": "1975-06-07"
},
{
"orbiting_body": "Mars",
"approach_date": "1935-06-07"
}
]
},
{
"id": "02",
"close_approach_data": [
{
"orbiting_body": "Earth",
"approach_date": "1945-06-07"
},
{
"orbiting_body": "Earth",
"approach_date": "1975-06-07"
},
{
"orbiting_body": "Mars",
"approach_date": "1935-06-07"
}
]
}
]
我想得到这个:
data = [
{
"id": "01",
"close_approach_data": {
"orbiting_body": "Mars",
"approach_date": "1935-06-07"
}
},
{
"id": "02",
"close_approach_data": {
"orbiting_body": "Mars",
"approach_date": "1935-06-07"
}
}
]
所以我试图想出一些代码:
earthObjs =[]
for element in data:
for subel in element["close_approach_data"]:
if ([subel][0]["orbiting_body"]=="Earth"):
#then i would have to store the objects
earthObjs.append([subel])
#here i am trying to find the object with the min 'approach_date'
minEarth = min(dt.strptime(earthObjs["close_approach_date"],"%Y-%m-%d"))
#then i would have to somehow place this as the only element of close_approach_data
element["close_approach_data"] = json.loads(minEarth)
#and clear the earthObjs list so it can be used for the next element
earthObjs.clear()
我很清楚我的代码有一半不起作用。我想我可能终于接近让它发挥作用了,我只是真的需要一些帮助。具体来说,我知道在搜索 min 时我做错了什么,因为我无法访问对象的 'close_approach_data'
字段。
另外,我也不确定 json.load 行。
最佳答案
这是将您描述的处理相当直接地转换为代码:
from datetime import datetime
import json
for dataset in data:
earliest, initial = datetime.max, {}
# Find the non-Earth body with the earliest approach date.
for close_approach in dataset["close_approach_data"]:
if close_approach["orbiting_body"] != "Earth":
dt = datetime.strptime(close_approach["approach_date"],
"%Y-%m-%d")
if dt < earliest:
dt, initial = earliest, close_approach
# Replace entire close_approach_data list with a single object
# comprised of the non-Earth item with the earliest date (or an
# empty dictionary if there weren't any).
dataset["close_approach_data"] = initial
print(json.dumps(data, indent=4))
输出:
[
{
"id": "01",
"close_approach_data": {
"orbiting_body": "Mars",
"approach_date": "1935-06-07"
}
},
{
"id": "02",
"close_approach_data": {
"orbiting_body": "Mars",
"approach_date": "1935-06-07"
}
}
]
关于python - 删除除具有最小日期的数组之外的所有嵌套 JSON 数组,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/50282616/