在 Python 中将 geojson 对象的一部分合并到另一个对象中
编辑：我试图在 Python 中操作 JSON 文件。在我的数据中，一些多边形有多个相关信息：坐标 ( LineString) 和面积百分比和面积(Text和Areain Point)，我想将它们组合成一个 JSON 对象。例如，来自文件的数据如下：
data = {
"type": "FeatureCollection",
"name": "entities",
"features": [{
"type": "Feature",
"properties": {
"Layer": "0",
"SubClasses": "AcDbEntity:AcDbBlockReference",
"EntityHandle": "2F1"
},
"geometry": {
"type": "LineString",
"coordinates": [
[61.971069681118479, 36.504485105673659],
[46.471068755199667, 36.504485105673659],
[46.471068755199667, 35.954489281866685],
[44.371068755199758, 35.954489281866685],
[44.371068755199758, 36.10448936390457],
[43.371069617387093, 36.104489150107824],
[43.371069617387093, 23.904496401184584],
[48.172716774891342, 23.904496401184584],
[48.171892994728751, 17.404489374370311],
[61.17106949647404, 17.404489281863786],
[61.17106949647404, 19.404489281863786],
[61.971069689453991, 19.404489282256687],
[61.971069681118479, 36.504485105673659]
]
}
},
{
"type": "Feature",
"properties": {
"Layer": "0",
"SubClasses": "AcDbEntity:AcDbMText",
"EntityHandle": "2F1",
"Text": "6%"
},
"geometry": {
"type": "Point",
"coordinates": [49.745686139884583, 28.11445704760262, 0.0]
}
},
我想将Point'sText和Areakey 和值组合到LineString基于EntityHandle's 的值，并删除 Point行。
哆啦的时光机2回答
-
婷婷同学_
像这样的例子：import jsondata = json.loads(json_data)features = data["features"]point_handle_text = { i["properties"]["EntityHandle"]: i["properties"]["Text"] for i in features if i["geometry"]["type"] == "Point"}combine_features = []for i in features: if i["geometry"]["type"] == "LineString": i["properties"]["Text"] = point_handle_text.get(i["properties"]["EntityHandle"]) combine_features.append(i)data["features"] = combine_featuresjson_data = json.dumps(data) -
弑天下
是的，可以在 python 中得到你的结果。它只需要将 json 数据存储到我们可以在 python 中使用的数据结构中，然后编写一个算法来组合具有相同实体类型的特征。我写了一个脚本来做到这一点，以及评论。程序从Point特征中提取文本属性并将其放入特征的属性中LineString。然后，我们基本上丢弃了Point。顺便说一句，您的 'before' json 数据有一个不应该在那里的尾随逗号。使用 Python 3.7.0：import jsonimport collectionsdef main(): with open('before_data.json') as f: before_data = json.load(f) # makes a python dict from the json file and stores in before features = before_data['features'] # list of features # loop through features, construct dictionary of entity handle mapped to point texts point_entities = collections.defaultdict() # to avoid 'if key not in' pattern for feature in features: entity_handle = feature['properties']['EntityHandle'] # only append points if feature['geometry']['type'] == 'Point': point_entities[entity_handle] = feature['properties']['Text'] merged_features = [] for feature in features: if feature['geometry']['type'] == 'LineString': entity_handle = feature['properties']['EntityHandle'] text_percent = point_entities[entity_handle] feature['properties']['Text'] = text_percent merged_features.append(feature) # print(json.dumps(before_data, indent=4)) result = before_data result['features'] = merged_features # compare with your expected output with open('after_data.json') as f: after_data = json.load(f) print(result == after_data) # returns True # finally, write your result to a file with open('result.json', 'w') as output_file: json.dump(result, output_file)if __name__ == '__main__': main()
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