Common graphs and digraphs generators (Cython)#
AUTHORS:
David Coudert (2012)
- sage.graphs.graph_generators_pyx.RandomGNP(n, p, directed=False, loops=False, seed=None)[source]#
Return a random graph or a digraph on \(n\) nodes.
Each edge is inserted independently with probability \(p\).
INPUT:
n
– number of nodes of the digraphp
– probability of an edgedirected
– boolean (default:False
); whether the random graph is directed or undirected (default)loops
– boolean (default:False
); whether the random digraph may have loops or not. This value is used only whendirected == True
seed
– arandom.Random
seed or a Pythonint
for the random number generator (default:None
)
REFERENCES:
EXAMPLES:
sage: from sage.graphs.graph_generators_pyx import RandomGNP sage: D = RandomGNP(10, .2, directed=True, seed=0) sage: D.num_verts() 10 sage: D.edges(sort=True, 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)]
>>> from sage.all import * >>> from sage.graphs.graph_generators_pyx import RandomGNP >>> D = RandomGNP(Integer(10), RealNumber('.2'), directed=True, seed=Integer(0)) >>> D.num_verts() 10 >>> D.edges(sort=True, 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)]