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SimplicialComplexes :: link

link -- link of a face in a simplicial complex



The link of a face $f$ in $D$ is the simplicial complex whose faces are the subsets $g$ whose intersection with $f$ is empty, where $f \cup g$ is a face of $D$.
i1 : R = QQ[x0,x1,x2,x3,x4,x5,x6];
i2 : D = simplicialComplex {x0*x1*x3, x1*x3*x4, x1*x2*x4, x2*x4*x5,
     	       x2*x3*x5, x3*x5*x6, x3*x4*x6, x0*x4*x6,
     	       x0*x4*x5, x0*x1*x5, x1*x5*x6, x1*x2*x6,
     	       x0*x2*x6, x0*x2*x3}

o2 = | x3x5x6 x1x5x6 x3x4x6 x0x4x6 x1x2x6 x0x2x6 x2x4x5 x0x4x5 x2x3x5 x0x1x5 x1x3x4 x1x2x4 x0x2x3 x0x1x3 |

o2 : SimplicialComplex
i3 : link(D,x0)

o3 = | x4x6 x2x6 x4x5 x1x5 x2x3 x1x3 |

o3 : SimplicialComplex
i4 : link(D,x0*x2)

o4 = | x6 x3 |

o4 : SimplicialComplex

See also

Ways to use link :

For the programmer

The object link is a method function.