nondescendants -- returns the nondescendants of a vertex of a digraph

Synopsis

• Usage:

  L = nondescendants (D, v)

• Inputs:
  • D, an instance of the type Digraph
  • v, a thing, a vertex of the digraph
• Outputs:
  • L, a set, a set of all the nondescendants of v

Description

i1 : D = digraph({a,b,c,d,e},{{a,b},{b,c},{b,d},{e,b}});

i2 : nondescendants (D, d)

o2 = set {a, b, c, e}

o2 : Set

See also

• children -- returns the children of a vertex of a digraph
• descendants -- returns the descendants of a digraph
• isReachable -- checks if a vertex u is reachable from a vertex v