Common graphs and digraphs generators (Cython)
AUTHORS:
Returns a random graph or a digraph on nodes. Each edge is inserted
independently with probability
.
INPUTS:
REFERENCES:
[1] |
|
[2] |
|
EXAMPLE:
sage: from sage.graphs.graph_generators_pyx import RandomGNP
sage: set_random_seed(0)
sage: D = RandomGNP(10, .2, directed = True)
sage: D.num_verts()
10
sage: D.edges(labels=False)
[(0, 2), (0, 5), (1, 5), (1, 7), (4, 1), (4, 2), (4, 9), (5, 0), (5, 2), (5, 3), (5, 7), (6, 5), (7, 1), (8, 2), (8, 6), (9, 4)]
TESTS:
sage: abs(mean([RandomGNP(200,.2).density() for i in range(30)])-.2) < .001
True
sage: RandomGNP(150,.2, loops = True)
Traceback (most recent call last):
...
ValueError: The 'loops' argument can be set to True only when 'directed' is True.