flagChains -- computes the maximal chains in a list of flags of a ranked poset

Synopsis

• Usage:

  C = flagChains(P, L)

• Inputs:
  • P, an instance of the type Poset,
  • L, a list, containing rank indices
• Outputs:
  • C, a list, all maximal chains of $P$ containing only elements in the flags indexed by $L$

Description

i1 : D = divisorPoset(2^2*3*5);

i2 : rankFunction D

o2 = {0, 1, 1, 2, 1, 2, 2, 3, 2, 3, 3, 4}

o2 : List

i3 : flagChains(D, {1,2,3})

o3 = {{2, 4, 12}, {2, 6, 12}, {3, 6, 12}, {2, 4, 20}, {2, 10, 20}, {5, 10,
     ------------------------------------------------------------------------
     20}, {2, 6, 30}, {3, 6, 30}, {2, 10, 30}, {5, 10, 30}, {3, 15, 30}, {5,
     ------------------------------------------------------------------------
     15, 30}}

o3 : List

See also

• flagPoset -- computes the subposet of specified ranks of a ranked poset
• isRanked -- determines if a poset is ranked
• maximalChains -- computes all maximal chains of a poset
• rankPoset -- generates a list of lists representing the ranks of a ranked poset