def main(directory, algorithm, file_type='png',
num_imgs=1, num_nodes=10, cell_length=10,
start_color=[0, 0, 0], act_color=[25, 25, 25]):
"""Print a picture of a graph's traversal permutations."""
start_color, act_color = [make_color(c) for c in (start_color, act_color)]
nodes = range(1, num_nodes + 1)
make_filename = filename_maker(directory, file_type)
print_graph = graph_printer(algorithm, cell_length)
for i in xrange(num_imgs):
G = randobj.random_connected_graph(nodes)
filename = make_filename(i, start_color, act_color)
print_graph(G, start_color, act_color, filename=filename)
def random_connected_graph(self):
"""A random choice from the set of connected graphs with at least n nodes."""
# A random connected graph can be chosen by first picking a random spanning tree,
# then choosing a random subset of edges uniformly from the set of edges not
# included in the tree.
min_n = self.config['min_n']
max_n = self.config['max_n']
sizes = range(min_n, max_n + 1)
distribution = self.node_distribution()
size = randobj.pick(sizes, distribution)
nodes = range(1, size + 1)
return randobj.random_connected_graph(nodes)