在去年完成我的osmnx论文工作后，我退回到Python PTSD一段时间了 . 但随着2017年ACS 5年预测的发布，我有一些新的数据分析要做 . 所以我将我的osmnx更新为0.8.2，做了conda更新--all -c conda-forge，并启动了我的旧笔记本 .

它主要起作用但我在graph_from_polygon函数中出错了 .

TypeError                                 Traceback (most recent call last)
<ipython-input-60-96e1e789c1a5> in <module>()
---> 58     network, network_stats, tract_polygon = load_network(optimal_tracts, utm_crs)
     59 

<ipython-input-56-3036c449a01f> in load_network(opt_tracts, my_crs)
     34 
---> 35     net = ox.core.graph_from_polygon(projected_circle,network_type='bike')
     36 

/Users/tom/anaconda/lib/python2.7/site-packages/osmnx/core.pyc in 
graph_from_polygon(polygon, network_type, simplify, retain_all, 
truncate_by_edge, name, timeout, memory, max_query_area_size, 
clean_periphery, infrastructure, custom_filter)
   1741    max_query_area_size=max_query_area_size,
   1742    infrastructure=infrastructure, custom_filter=custom_filter)
-> 1743         G_buffered = create_graph(response_jsons, name=name, 
retain_all=True, network_type=network_type)
   1744         G_buffered = truncate_graph_polygon(G_buffered, 
polygon_buffered, retain_all=True, truncate_by_edge=truncate_by_edge)
   1745 

/Users/tom/anaconda/lib/python2.7/site-packages/osmnx/core.pyc in 
create_graph(response_jsons, name, retain_all, network_type)
   1358     # add length (great circle distance between nodes) attribute to each edge to
   1359     # use as weight
-> 1360     if len(G.edges) > 0:
   1361         G = add_edge_lengths(G)
   1362 

TypeError: object of type 'instancemethod' has no len()

直到这一刻，包裹仍然很好地一起玩 . projected_circle 似乎被正确创建为UTM纬度 - 多边形（epsg：32617，测试城市夏洛特，北卡罗来纳州） . 这是相关的代码 . （ opt_tracts 是一组人口普查区域的GeoDataFrame） .

def load_network(opt_tracts,my_crs):    

 tract_poly=opt_tracts.unary_union

 projected_circle,projection = ox.projection.project_geometry(tract_poly,crs={'init': my_crs}, to_latlong=True)

 net = ox.core.graph_from_polygon(projected_circle,network_type='bike')

 net_stats = ox.stats.basic_stats(net,area=8047)

 return (net, net_stats, tract_poly)

这是控制台输出：

Got all network data within polygon from API in 1 request(s) and 0.61 seconds
Creating networkx graph from downloaded OSM data...
Created graph with 11,371 nodes and 22,550 edges in 1.10 seconds
python osmnx