pythonmatplotlibnetworkxnetgraph

Adjust fontsize in netgraph with nodes in form of proposition with quantifiers?

I am using netgraph to visualize my networkx graphs. My problem now is, the visualisation of formulas are in natural way not as pretty as I would expect. Here my example graph:

import networkx as nx
from netgraph import Graph # pip install netgraph
import matplotlib.pyplot as plt

node_labels = {1: 'p→q', 2: '¬q', 3: '¬ (¬p)', 4: '¬p', 5: '¬p∧ ¬ (¬p)', 6: 'p', 7: 'q', 8: 'q∧ ¬q', 9: '¬p'}
color_map = {1: 'red', 2: 'red', 3: 'red', 4: 'red', 5: 'lightblue', 6: 'lightblue', 7: 'lightblue', 8: 'lightblue', 9: 'blue'}
edge_labels = {(3, 5): '∧I', (4, 5): '∧I', (4, 6): '¬E', (5, 6): '¬E', (1, 7): '→E', (6, 7): '→E', (2, 8): '∧I', (7, 8): '∧I', (8, 9): '¬E', (3, 9): '¬E'}

graph = nx.from_edgelist(edge_labels, nx.DiGraph())


Graph(graph, node_labels=node_labels, edge_labels=edge_labels,
      node_color=color_map, node_edge_color=color_map, arrows=True)

plt.show()

Output (direct / after zoom in):

enter image description here enter image description here:

My questions now:

Solution

  • By default, iff node labels are plotted on top of nodes (i.e. without an offset), netgraph scales the node label font size such that all labels fit within their respective node artists. However, this behaviour can be overridden by specifying the font size explicitly , e.g. using node_label_fontdict(size=20).

    The rotation of the edge labels can be turned off setting the edge_label_rotate = False flag.

    enter image description here

    #!/usr/bin/env python
# coding: utf-8

import matplotlib.pyplot as plt
import networkx as nx

from netgraph import Graph # pip install netgraph

node_labels = {1: 'p→q', 2: '¬q', 3: '¬ (¬p)', 4: '¬p', 5: '¬p∧ ¬ (¬p)', 6: 'p', 7: 'q', 8: 'q∧ ¬q', 9: '¬p'}
color_map = {1: 'red', 2: 'red', 3: 'red', 4: 'red', 5: 'lightblue', 6: 'lightblue', 7: 'lightblue', 8: 'lightblue', 9: 'blue'}
edge_labels = {(3, 5): '∧I', (4, 5): '∧I', (4, 6): '¬E', (5, 6): '¬E', (1, 7): '→E', (6, 7): '→E', (2, 8): '∧I', (7, 8): '∧I', (8, 9): '¬E', (3, 9): '¬E'}

graph = nx.from_edgelist(edge_labels, nx.DiGraph())

Graph(graph, node_layout='dot',
      node_labels=node_labels, node_label_fontdict=dict(size=21),
      edge_labels=edge_labels, edge_label_fontdict=dict(size=14), edge_label_rotate=False,
      node_color=color_map, node_edge_color=color_map, arrows=True
)

plt.show()