Plotly with directed arrows as annotations

plotly_with_arrow.py

import math
import plotly.offline as py
from plotly.graph_objs import *

py.init_notebook_mode(connected=True)
%matplotlib inline

import networkx as nx

G=nx.random_geometric_graph(200,0.125)
pos=nx.get_node_attributes(G,'pos')

dmin=1
ncenter=0
for n in pos:
    x,y=pos[n]
    d=(x-0.5)**2+(y-0.5)**2
    if d<dmin:
        ncenter=n
        dmin=d

p=nx.single_source_shortest_path_length(G,ncenter)


node_trace = Scatter(
    x=[],
    y=[],
    text=[],
    mode='markers',
    hoverinfo='text',
    marker=Marker(
        showscale=True,
        # colorscale options
        # 'Greys' | 'Greens' | 'Bluered' | 'Hot' | 'Picnic' | 'Portland' |
        # Jet' | 'RdBu' | 'Blackbody' | 'Earth' | 'Electric' | 'YIOrRd' | 'YIGnBu'
        colorscale='YIGnBu',
        reversescale=True,
        color=[],
        size=10,
        colorbar=dict(
            thickness=15,
            title='Node Connections',
            xanchor='left',
            titleside='right'
        ),
        line=dict(width=2)))

for node in G.nodes():
    x, y = G.node[node]['pos']
    node_trace['x'].append(x)
    node_trace['y'].append(y)

for node, adjacencies in enumerate(G.adjacency_list()):
    node_trace['marker']['color'].append(len(adjacencies))
    node_info = '# of connections: '+str(len(adjacencies))
    node_trace['text'].append(node_info)

# initialize a list of edge traces
edge_trace = []
marker_size=5

for edge in G.edges():
    x0, y0 = G.node[edge[0]]['pos']
    x1, y1 = G.node[edge[1]]['pos']
    edge_trace.append(dict(x=x1,
                           y=y1,
                           ax=x0,
                           ay=y0,
                           axref='x',
                           ayref='y',
                           showarrow=True,
                           arrowwidth=2,
                           arrowcolor='#2a3855'
                           )
                      )
    
fig = Figure(data=Data([node_trace]),
             layout=Layout(
                title='<br>Network graph made with Python',
                titlefont=dict(size=16),
                showlegend=False,
                hovermode='closest',
                margin=dict(b=20,l=5,r=5,t=40),
                annotations=edge_trace,
                xaxis=XAxis(showgrid=False, zeroline=False, showticklabels=False),
                yaxis=YAxis(showgrid=False, zeroline=False, showticklabels=False)))

py.iplot(fig, filename='networkx')