TypeError: unhashable type: 'LineString' 使用 ox.simplify_graph() 时

如何解决TypeError: unhashable type: 'LineString' 使用 ox.simplify_graph() 时

我有数据集，我从中构建了一个 NetworkX 兼容图。 shapefile 已转换为节点和边的字典，然后已转换为 GeoDataFrame。从那时起，我使用 ox.graph_from_gdfs() 来创建功能图。边 GeoDataFrame 看起来像这样（第一行，简化）：

            | id     | ref  | name  | speedlim | length|  geometry                          | u    | v   | key
1193,2716,0 | 11452  | ref1 | name1 | 50       | 15    |  LInesTRING (10.5 60.4,10.5 60.4) | 1193 | 2716| 0

而节点 GeoDataFrame 看起来像这样：

       | x    | y     | id    | geometry     
111604 | 10.5 | 60.4  | 11604 | POINT (10.5 60.4)

将这些转换为 MultiDiGraph 不会返回错误：

G = ox.graph_from_gdfs(gdf_nodes,gdf_edges)

从图形转换回 gdfs 时也会返回相同的数据。

但是，在简化 G 时，会出现以下错误：

G = ox.simplify_graph(G)

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-18-e400610fe7d3> in <module>
----> 1 F = ox.simplify_graph(G)

~\anaconda3\envs\ox\lib\site-packages\osmnx\simplification.py in simplify_graph(G,strict,remove_rings)
    276         for key in edge_attributes:
    277             # don't touch the length attribute,we'll sum it at the end
--> 278             if len(set(edge_attributes[key])) == 1 and not key == "length":
    279                 # if there's only 1 unique value in this attribute list,280                 # consolidate it to the single value (the zero-th)

**TypeError: unhashable type: 'Linestring'**

我的猜测是 gdf_nodes 和 gdf_edges 中的部分数据格式不正确，或者缺少某些内容。但是，我无法弄清楚是什么。除了使用此功能外，我没有遇到 OSMnx 的任何其他错误。

编辑 1：

这是一个重现错误的简单代码

import geopandas as gpd
import osmnx as ox
import networkx as nx
from shapely.geometry import Point,Linestring


# Sample dictionary containing edge data (copy from first elements in dataset)
edges_test = {
    (111603,111604,0) : {"id": 11452,"ref":"Mohagavegen","name":"Mohagavegen","speedlim":50,"length":15.1,"geometry":Linestring([(10.55351,60.40720),(10.55375,60.40714)]),"u":111603,"v":111604,"key":0},(111604,111605,0) : {"id": 11453,"length":120.8,"geometry":Linestring([Point(10.553752594,60.407140812),Point(10.554987804,60.406802271),Point(10.555623630,60.406579470)]),"u":111604,"v":111605,(111605,111606,0) : {"id": 11454,"length":14.2,"geometry":Linestring([Point(10.55562,60.40658),Point(10.55584,60.40651)]),"u":111605,"v":111606,"key":0}
}


# Sample dictionary containing node data (copy from first elements in dataset)
nodes_test = {
    11603: {"x":10.5538,"y":60.4071,"id":111603,"geometry":Point((10.55375,60.40714))},11604: {"x":10.5538,"id":111604,11605: {"x":10.5556,"y":60.4066,"id":111605,"geometry":Point((10.5556,60.4066))},11606: {"x":10.5558,"y":60.4065,"id":111606,"geometry":Point((10.5558,60.4065))}
}


# Convert edges into geodataframe
gdf_edges = gpd.GeoDataFrame(edges_test,crs = crs).T
gdf_edges = gpd.GeoDataFrame(
    edges_df,geometry=gdf_edges['geometry'])

# Convert nodes into geodataframe
gdf_nodes = gpd.GeoDataFrame(nodes_test,crs = crs).T
gdf_nodes = gpd.GeoDataFrame(
    nodes_df,geometry=gdf_nodes['geometry'])

# Build graph from geodataframes 
F = ox.graph_from_gdfs(gdf_nodes,gdf_edges)

# Plotting will show that there is one intersectial node present
# ox.plot_graph(F)

# Simplify graph
F = ox.simplify_graph(F)

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-113-f81732e4921a> in <module>
     41 
     42 # Simplify graph
---> 43 F = ox.simplify_graph(F)

~\anaconda3\envs\ox\lib\site-packages\osmnx\simplification.py in simplify_graph(G,280                 # consolidate it to the single value (the zero-th)

TypeError: unhashable type: 'Linestring'

我怀疑存在一些具有不同 ID 的重复节点（请参阅 x,y 以获取 111603 和 111604）。也许这可能是问题所在？

解决方法

正如 Obeq 所指出的，解决方案是删除包含 Linestring 的属性。

遵循 https://stackoverflow.com/questions/50314296/pythonic-way-to-delete-edge-attributes 中的解决方案：

att_list = ['geometry']
for n1,n2,d in G.edges(data=True):
    for att in att_list:
        d.pop(att,None)

# Simplify after removing attribute
G = ox.simplify_graph(G)