我有一个包含以下数据的 json(test.json) 文件。我有大约 10000 条记录。我需要将 value 从字符串转换为浮点写入新文件 (test1.json)。我如何从 Python 执行此操作？
{
"name":"test001",
"cat":"test",
"loc":"x loc",
"ings":[
{
"name":"rrrrrr",
"value":"13.0"
},
{
"name":"hhhh",
"value":"18.0"
}
],
"nums":[
{
"name":"kkkk",
"value":"82.05"
},
{
"name":"uuuuu",
"value":"53.55"
}
]
},
{
"name":"test002",
"cat":"test1",
"loc":"y loc",
"ings":[
{
"name":"trtrtr",
"value":"11.0"
},
{
"name":"wewew",
"value":"19.0"
}
],
"nums":[
{
"name":"iuyt",
"value":"122.05"
},
{
"name":"oiui",
"value":"15.5"
}
]
}
生成的 json 文件(test1.json)应该如下所示...
{
"name":"test001",
"cat":"test",
"loc":"x loc",
"ings":[
{
"name":"rrrrrr",
"value":13.0
},
{
"name":"hhhh",
"value":18.0
}
],
"nums":[
{
"name":"kkkk",
"value":82.05
},
{
"name":"uuuuu",
"value":53.55
}
]
},
{
"name":"test002",
"cat":"test1",
"loc":"y loc",
"ings":[
{
"name":"trtrtr",
"value":11.0
},
{
"name":"wewew",
"value":19.0
}
],
"nums":[
{
"name":"iuyt",
"value":122.05
},
{
"name":"oiui",
"value":15.5
}
]
}
最佳答案
您可以为 json.loads 提供一个 object_hook允许您修改在 json 中找到的任何对象(字典)的方法:
import json
json_data = """
[{
"name":"test001",
"cat":"test",
"loc":"x loc",
"ings":[
{
"name":"rrrrrr",
"value":"13.0"
},
{
"name":"hhhh",
"value":"18.0"
}
],
"nums":[
{
"name":"kkkk",
"value":"82.05"
},
{
"name":"uuuuu",
"value":"53.55"
}
]
},
{
"name":"test002",
"cat":"test1",
"loc":"y loc",
"ings":[
{
"name":"trtrtr",
"value":"11.0"
},
{
"name":"wewew",
"value":"19.0"
}
],
"nums":[
{
"name":"iuyt",
"value":"122.05"
},
{
"name":"oiui",
"value":"15.5"
}
]
}]
"""
def as_float(obj):
"""Checks each dict passed to this function if it contains the key "value"
Args:
obj (dict): The object to decode
Returns:
dict: The new dictionary with changes if necessary
"""
if "value" in obj:
obj["value"] = float(obj["value"])
return obj
if __name__ == '__main__':
l = json.loads(json_data, object_hook=as_float)
print (json.dumps(l, indent=4))
这会产生您想要的结果:
[
{
"loc": "x loc",
"ings": [
{
"name": "rrrrrr",
"value": 13.0
},
{
"name": "hhhh",
"value": 18.0
}
],
"name": "test001",
"nums": [
{
"name": "kkkk",
"value": 82.05
},
{
"name": "uuuuu",
"value": 53.55
}
],
"cat": "test"
},
{
"loc": "y loc",
"ings": [
{
"name": "trtrtr",
"value": 11.0
},
{
"name": "wewew",
"value": 19.0
}
],
"name": "test002",
"nums": [
{
"name": "iuyt",
"value": 122.05
},
{
"name": "oiui",
"value": 15.5
}
],
"cat": "test1"
}
]
改为写入文件:
with open("out.json", "w+") as out:
json.dump(l, out, indent=4)
关于python - 将float字符串转换为json中的float，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/36672886/