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fvector -- Returns the F-vector of a complex

Synopsis

Description

Compute the F-vector of a simplicial Complex C.

i1 : K=QQ;
i2 : R=K[x_0..x_4]

o2 = R

o2 : PolynomialRing
i3 : I=ideal(x_0*x_1,x_1*x_2,x_2*x_3,x_3*x_4,x_4*x_0)

o3 = ideal (x x , x x , x x , x x , x x )
             0 1   1 2   2 3   3 4   0 4

o3 : Ideal of R
i4 : C=idealToComplex I

o4 = {x  x  , x  x  , x  x  , x  x  , x  x  }
       2  4    0  3    0  2    1  3    1  4

o4 : complex with 5 facets on the vertices x  x  x  x  x  
                                            0  1  2  3  4
i5 : fvector(C)

o5 = {1, 5, 5, 0, 0, 0}

o5 : List

See also

  • Complex -- The class of all simplicial complexes.
  • Face -- The class of faces of simplicial complexes.
  • faces -- Returns the faces of a complex
  • idealToComplex -- Compute the Stanley-Reisner complex.

Ways to use fvector :

  • fvector(Complex)