Spaces:
Runtime error
Runtime error
| """ | |
| ===== | |
| Roget | |
| ===== | |
| Build a directed graph of 1022 categories and 5075 cross-references as defined | |
| in the 1879 version of Roget's Thesaurus. This example is described in Section | |
| 1.2 of | |
| Donald E. Knuth, "The Stanford GraphBase: A Platform for Combinatorial | |
| Computing", ACM Press, New York, 1993. | |
| http://www-cs-faculty.stanford.edu/~knuth/sgb.html | |
| Note that one of the 5075 cross references is a self loop yet it is included in | |
| the graph built here because the standard networkx `DiGraph` class allows self | |
| loops. (cf. 400pungency:400 401 403 405). | |
| The data file can be found at: | |
| - https://github.com/networkx/networkx/blob/main/examples/graph/roget_dat.txt.gz | |
| """ | |
| import gzip | |
| import re | |
| import sys | |
| import matplotlib.pyplot as plt | |
| import networkx as nx | |
| def roget_graph(): | |
| """Return the thesaurus graph from the roget.dat example in | |
| the Stanford Graph Base. | |
| """ | |
| # open file roget_dat.txt.gz | |
| fh = gzip.open("roget_dat.txt.gz", "r") | |
| G = nx.DiGraph() | |
| for line in fh.readlines(): | |
| line = line.decode() | |
| if line.startswith("*"): # skip comments | |
| continue | |
| if line.startswith(" "): # this is a continuation line, append | |
| line = oldline + line | |
| if line.endswith("\\\n"): # continuation line, buffer, goto next | |
| oldline = line.strip("\\\n") | |
| continue | |
| (headname, tails) = line.split(":") | |
| # head | |
| numfind = re.compile(r"^\d+") # re to find the number of this word | |
| head = numfind.findall(headname)[0] # get the number | |
| G.add_node(head) | |
| for tail in tails.split(): | |
| if head == tail: | |
| print("skipping self loop", head, tail, file=sys.stderr) | |
| G.add_edge(head, tail) | |
| return G | |
| G = roget_graph() | |
| print("Loaded roget_dat.txt containing 1022 categories.") | |
| print(G) | |
| UG = G.to_undirected() | |
| print(nx.number_connected_components(UG), "connected components") | |
| options = { | |
| "node_color": "black", | |
| "node_size": 1, | |
| "edge_color": "gray", | |
| "linewidths": 0, | |
| "width": 0.1, | |
| } | |
| nx.draw_circular(UG, **options) | |
| plt.show() | |