Python 如何使用networkx绘制社区
如何使用python networkx绘制社区图,如下图所示:Python 如何使用networkx绘制社区,python,graph,networkx,Python,Graph,Networkx,如何使用python networkx绘制社区图,如下图所示: 有关networkx.draw\u networkx\u节点和networkx.draw\u networkx\u边的文档说明了如何设置节点和边的颜色。可以通过查找每个社区的节点位置,然后绘制包含所有位置(以及部分位置)的面片(例如,matplotlib.patches.Circle)来创建社区边界面片 难点在于图形布局/设置节点位置。 顺便说一句,networkx中没有实现“开箱即用”所需图形布局的例程。您希望执行以下操作: 相
有关
networkx.draw\u networkx\u节点和networkx.draw\u networkx\u边的文档说明了如何设置节点和边的颜色。可以通过查找每个社区的节点位置,然后绘制包含所有位置(以及部分位置)的面片(例如,matplotlib.patches.Circle
)来创建社区边界面片
难点在于图形布局/设置节点位置。
顺便说一句,networkx中没有实现“开箱即用”所需图形布局的例程。您希望执行以下操作:
相对于彼此定位社区:创建一个新的加权图,其中每个节点对应一个社区,权重对应于社区之间的边数。使用您喜爱的图形布局算法(例如,spring\u布局
)获得一个像样的布局
在每个社区中定位节点:为每个社区创建一个新的图形。查找子图的布局
组合1)和3)中的节点位置。例如,按1)中的系数10计算社区职位;将这些值添加到该社区中所有节点的位置(如2中计算的)
我一直想实现这一点有一段时间了。我可能今天晚些时候或者周末做
编辑:
瞧。现在,您只需要在节点周围(后面)绘制您最喜欢的补丁
补遗
虽然总体思路是合理的,但我上面的旧实现存在一些问题。最重要的是,对于规模不均的社区,实施效果并不理想。具体来说,\u position\u communities
在画布上为每个社区提供相同数量的不动产。如果一些社区比其他社区大得多,那么这些社区最终会被压缩到与小社区相同的空间中。显然,这并不能很好地反映图形的结构
我写了一个可视化网络的库,叫做。它包括上述社区布局例程的改进版本,在安排社区时还考虑了社区的大小。它与networkx
和igraph
图形对象完全兼容,因此制作美观的图形应该简单快捷(至少是这样)
哇!这是个好主意。感谢您的实施倒数第二行需要是nx.draw(g,pos,node_color=list(partition.values())
@mortezashahrarinia谢谢您的提醒。显然,他们改变了分区的类型。现在变了。
import numpy as np
import matplotlib.pyplot as plt
import networkx as nx
def community_layout(g, partition):
"""
Compute the layout for a modular graph.
Arguments:
----------
g -- networkx.Graph or networkx.DiGraph instance
graph to plot
partition -- dict mapping int node -> int community
graph partitions
Returns:
--------
pos -- dict mapping int node -> (float x, float y)
node positions
"""
pos_communities = _position_communities(g, partition, scale=3.)
pos_nodes = _position_nodes(g, partition, scale=1.)
# combine positions
pos = dict()
for node in g.nodes():
pos[node] = pos_communities[node] + pos_nodes[node]
return pos
def _position_communities(g, partition, **kwargs):
# create a weighted graph, in which each node corresponds to a community,
# and each edge weight to the number of edges between communities
between_community_edges = _find_between_community_edges(g, partition)
communities = set(partition.values())
hypergraph = nx.DiGraph()
hypergraph.add_nodes_from(communities)
for (ci, cj), edges in between_community_edges.items():
hypergraph.add_edge(ci, cj, weight=len(edges))
# find layout for communities
pos_communities = nx.spring_layout(hypergraph, **kwargs)
# set node positions to position of community
pos = dict()
for node, community in partition.items():
pos[node] = pos_communities[community]
return pos
def _find_between_community_edges(g, partition):
edges = dict()
for (ni, nj) in g.edges():
ci = partition[ni]
cj = partition[nj]
if ci != cj:
try:
edges[(ci, cj)] += [(ni, nj)]
except KeyError:
edges[(ci, cj)] = [(ni, nj)]
return edges
def _position_nodes(g, partition, **kwargs):
"""
Positions nodes within communities.
"""
communities = dict()
for node, community in partition.items():
try:
communities[community] += [node]
except KeyError:
communities[community] = [node]
pos = dict()
for ci, nodes in communities.items():
subgraph = g.subgraph(nodes)
pos_subgraph = nx.spring_layout(subgraph, **kwargs)
pos.update(pos_subgraph)
return pos
def test():
# to install networkx 2.0 compatible version of python-louvain use:
# pip install -U git+https://github.com/taynaud/python-louvain.git@networkx2
from community import community_louvain
g = nx.karate_club_graph()
partition = community_louvain.best_partition(g)
pos = community_layout(g, partition)
nx.draw(g, pos, node_color=list(partition.values())); plt.show()
return
import matplotlib.pyplot as plt
import networkx as nx
# installation easiest via pip:
# pip install netgraph
from netgraph import Graph
# create a modular graph
partition_sizes = [10, 20, 30, 40]
g = nx.random_partition_graph(partition_sizes, 0.5, 0.1)
# since we created the graph, we know the best partition:
node_to_community = dict()
node = 0
for community_id, size in enumerate(partition_sizes):
for _ in range(size):
node_to_community[node] = community_id
node += 1
# # alternatively, we can infer the best partition using Louvain:
# from community import community_louvain
# node_to_community = community_louvain.best_partition(g)
community_to_color = {
0 : 'tab:blue',
1 : 'tab:orange',
2 : 'tab:green',
3 : 'tab:red',
}
node_color = {node: community_to_color[community_id] for node, community_id in node_to_community.items()}
Graph(g,
node_color=node_color, node_edge_width=0, edge_alpha=0.1,
node_layout='community', node_layout_kwargs=dict(node_to_community=node_to_community),
edge_layout='bundled', edge_layout_kwargs=dict(k=2000),
)
plt.show()