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Polyhedra :: fan(Matrix,Matrix,List)

fan(Matrix,Matrix,List) -- Constructing a fan.

Synopsis

Description

Basic constructor for fans that takes a matrix containing the rays of the fan and a list of lists with the indices of the rays in the maximal cones. Optionally one may provide a lineality space.

This constructor does not check well-definedness, see isWellDefined.

i1 : M = matrix{{1,0},{0,1}}

o1 = | 1 0 |
     | 0 1 |

              2        2
o1 : Matrix ZZ  <--- ZZ
i2 : L = {{0,1}}

o2 = {{0, 1}}

o2 : List
i3 : F = fan(M,L)

o3 = F

o3 : Fan
i4 : N = matrix{{1},{1}}

o4 = | 1 |
     | 1 |

              2        1
o4 : Matrix ZZ  <--- ZZ
i5 : F1 = fan(M,N,L)

o5 = F1

o5 : Fan