我正在尝试使用folium做一个等值线，它提供了GeoJSON，Pandas和传单之间的良好链接。
GeoJSON格式如下：
{
"type":"FeatureCollection",
"features":[
{
"type":"Feature",
"geometry":
{
"type":"Polygon",
"coordinates":[[[-1.6704591323124895,49.62681486270549], .....
{
"insee":"50173",
"nom":"Équeurdreville-Hainneville",
"wikipedia":"fr:Équeurdreville-Hainneville",
"surf_m2":12940306}},
Pandas DataFrame：
postal_count.head(5)
Out[98]:
Code_commune_INSEE CP_count
0 75120 723
1 75115 698
2 75112 671
3 75118 627
4 75111 622
“Code_communes_INSEE”对应于GeoJSON中的属性“insee”。我想在上面的DataFrame中使用变量“CP_count”做一个等值线。
这是我的代码（来自this notebook的代码段）
map_france = folium.Map(location=[47.000000, 2.000000], zoom_start=6)
map_france.choropleth(
geo_str=open(geo_path + 'simplified_communes100m.json').read(),
data=postal_count,
columns=['Code_commune_INSEE', 'CP_count'],
key_on='feature.geometry.properties.insee',
fill_color='YlGn',
)
map_france.save(table_path + 'choro_test1.html')
我仍然一次又一次地收到此错误：
---------------------------------------------------------------------------
AttributeError Traceback (most recent call last)
<ipython-input-83-ea0fd2c1c207> in <module>()
8 fill_color='YlGn',
9 )
---> 10 map_france.save('/media/flo/Stockage/Data/MesAides/map/choro_test1.html')
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/element.py in save(self, outfile, close_file, **kwargs)
151
152 root = self.get_root()
--> 153 html = root.render(**kwargs)
154 fid.write(html.encode('utf8'))
155 if close_file:
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/element.py in render(self, **kwargs)
357 """Renders the HTML representation of the element."""
358 for name, child in self._children.items():
--> 359 child.render(**kwargs)
360 return self._template.render(this=self, kwargs=kwargs)
361
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/element.py in render(self, **kwargs)
665
666 for name, element in self._children.items():
--> 667 element.render(**kwargs)
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/element.py in render(self, **kwargs)
661 script = self._template.module.__dict__.get('script', None)
662 if script is not None:
--> 663 figure.script.add_children(Element(script(self, kwargs)),
664 name=self.get_name())
665
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/jinja2/runtime.py in __call__(self, *args, **kwargs)
434 raise TypeError('macro %r takes not more than %d argument(s)' %
435 (self.name, len(self.arguments)))
--> 436 return self._func(*arguments)
437
438 def __repr__(self):
<template> in macro(l_this, l_kwargs)
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/jinja2/runtime.py in call(_Context__self, _Context__obj, *args, **kwargs)
194 args = (__self.environment,) + args
195 try:
--> 196 return __obj(*args, **kwargs)
197 except StopIteration:
198 return __self.environment.undefined('value was undefined because '
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/features.py in style_data(self)
352
353 for feature in self.data['features']:
--> 354 feature.setdefault('properties', {}).setdefault('style', {}).update(self.style_function(feature)) # noqa
355 return json.dumps(self.data, sort_keys=True)
356
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/folium.py in style_function(x)
671 "color": line_color,
672 "fillOpacity": fill_opacity,
--> 673 "fillColor": color_scale_fun(x)
674 }
675
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/folium.py in color_scale_fun(x)
659 def color_scale_fun(x):
660 return color_range[len(
--> 661 [u for u in color_domain if
662 u <= color_data[get_by_key(x, key_on)]])]
663 else:
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/folium.py in <listcomp>(.0)
660 return color_range[len(
661 [u for u in color_domain if
--> 662 u <= color_data[get_by_key(x, key_on)]])]
663 else:
664 def color_scale_fun(x):
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/folium.py in get_by_key(obj, key)
655 return (obj.get(key, None) if len(key.split('.')) <= 1 else
656 get_by_key(obj.get(key.split('.')[0], None),
--> 657 '.'.join(key.split('.')[1:])))
658
659 def color_scale_fun(x):
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/folium.py in get_by_key(obj, key)
655 return (obj.get(key, None) if len(key.split('.')) <= 1 else
656 get_by_key(obj.get(key.split('.')[0], None),
--> 657 '.'.join(key.split('.')[1:])))
658
659 def color_scale_fun(x):
/home/flo/.virtualenvs/mesaides/lib/python3.4/site-packages/folium/folium.py in get_by_key(obj, key)
653
654 def get_by_key(obj, key):
--> 655 return (obj.get(key, None) if len(key.split('.')) <= 1 else
656 get_by_key(obj.get(key.split('.')[0], None),
657 '.'.join(key.split('.')[1:])))
AttributeError: 'NoneType' object has no attribute 'get'
我尝试使用key_on='feature.geometry.properties.insee'但没有取得任何成功。
答案 0 :(得分：3)
有两个问题：
1 - 正确访问＆＃39; insee＆＃39;参数是：key_on='feature.properties.insee'
找到正确的key_on的最佳方法是使用geoJSON dict来确保您正在调用正确的属性。
2-一旦你有了正确的key_on参数，你需要确保你的Pandas DataFrame中包含 geoJSON中所有可用的密钥（否则会引发{ {1}}）
在这种情况下，我使用以下命令行来获取我的geoJSON包含的所有KeyError个键：
insee如果您遇到同样的问题，这可以解决您的问题。
答案 1 :(得分：0)
我在JupyterLab上使用Folium 0.5.0遇到了相同的问题（在labs.cognitiveclass.ai上）。然后，我复制了代码并在PyCharm中运行了它，它起作用了！我不明白为什么，也许有一些后端问题（？）
如果要在Jupyter笔记本之外显示大叶地图，则必须将地图保存为html：
map_france.save('map_france.html')
并在浏览器中打开html。