本文整理汇总了Python中sage.graphs.digraph.DiGraph.neighbors_in方法的典型用法代码示例。如果您正苦于以下问题：Python DiGraph.neighbors_in方法的具体用法？Python DiGraph.neighbors_in怎么用？Python DiGraph.neighbors_in使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类sage.graphs.digraph.DiGraph的用法示例。
在下文中一共展示了DiGraph.neighbors_in方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: reduced_rauzy_graph
# 需要导入模块: from sage.graphs.digraph import DiGraph [as 别名]
# 或者: from sage.graphs.digraph.DiGraph import neighbors_in [as 别名]
#.........这里部分代码省略.........
in the reduced Rauzy graph of order `n` whose label is the label of
the path in `G_n`.
.. NOTE::
In the case of infinite recurrent non periodic words, this
definition correspond to the following one that can be found in
[1] and [2] where a simple path is a path that begins with a
special factor, ends with a special factor and contains no
other vertices that are special:
The reduced Rauzy graph of factors of length `n` is obtained
from `G_n` by replacing each simple path `P=v_1 v_2 ...
v_{\ell}` with an edge `v_1 v_{\ell}` whose label is the
concatenation of the labels of the edges of `P`.
EXAMPLES::
sage: w = Word(range(10)); w
word: 0123456789
sage: g = w.reduced_rauzy_graph(3); g
Looped multi-digraph on 2 vertices
sage: g.vertices()
[word: 012, word: 789]
sage: g.edges()
[(word: 012, word: 789, word: 3456789)]
For the Fibonacci word::
sage: f = words.FibonacciWord()[:100]
sage: g = f.reduced_rauzy_graph(8);g
Looped multi-digraph on 2 vertices
sage: g.vertices()
[word: 01001010, word: 01010010]
sage: g.edges()
[(word: 01001010, word: 01010010, word: 010), (word: 01010010, word: 01001010, word: 01010), (word: 01010010, word: 01001010, word: 10)]
For periodic words::
sage: from itertools import cycle
sage: w = Word(cycle('abcd'))[:100]
sage: g = w.reduced_rauzy_graph(3)
sage: g.edges()
[(word: abc, word: abc, word: dabc)]
::
sage: w = Word('111')
sage: for i in range(5) : w.reduced_rauzy_graph(i)
Looped digraph on 1 vertex
Looped digraph on 1 vertex
Looped digraph on 1 vertex
Looped multi-digraph on 1 vertex
Looped multi-digraph on 0 vertices
For ultimately periodic words::
sage: sigma = WordMorphism('a->abcd,b->cd,c->cd,d->cd')
sage: w = sigma.fixed_point('a')[:100]; w
word: abcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcd...
sage: g = w.reduced_rauzy_graph(5)
sage: g.vertices()
[word: abcdc, word: cdcdc]
sage: g.edges()
[(word: abcdc, word: cdcdc, word: dc), (word: cdcdc, word: cdcdc, word: dc)]
AUTHOR:
Julien Leroy (March 2010): initial version
REFERENCES:
- [1] M. Bucci et al. A. De Luca, A. Glen, L. Q. Zamboni, A
connection between palindromic and factor complexity using
return words," Advances in Applied Mathematics 42 (2009) 60-74.
- [2] L'ubomira Balkova, Edita Pelantova, and Wolfgang Steiner.
Sequences with constant number of return words. Monatsh. Math,
155 (2008) 251-263.
"""
from sage.graphs.all import DiGraph
from copy import copy
g = copy(self.rauzy_graph(n))
# Otherwise it changes the rauzy_graph function.
l = [v for v in g if g.in_degree(v)==1 and g.out_degree(v)==1]
if g.num_verts() !=0 and len(l)==g.num_verts():
# In this case, the Rauzy graph is simply a cycle.
g = DiGraph()
g.allow_loops(True)
g.add_vertex(self[:n])
g.add_edge(self[:n],self[:n],self[n:n+len(l)])
else:
g.allow_loops(True)
g.allow_multiple_edges(True)
for v in l:
[i] = g.neighbors_in(v)
[o] = g.neighbors_out(v)
g.add_edge(i,o,g.edge_label(i,v)[0]*g.edge_label(v,o)[0])
g.delete_vertex(v)
return g