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# fc -- The faces of a complex.

- Usage:
    `fc(C)`
    `fc(C,d)`
- Inputs:
  - C, an embedded complex,
  - d, an integer, positive
- Outputs:
  - a list,

## Description

Returns a list with entries lists with the faces of C starting in dimension -1. If d is given then faces of dimension d are returned.

    i1 : R=QQ[x_0..x_5]

    o1 = R

    o1 : PolynomialRing

    i2 : C=boundaryCyclicPolytope(3,R)

    o2 = 2: x x x  x x x  x x x  x x x  x x x  x x x  x x x  x x x
             0 1 2  0 2 3  0 3 4  0 1 5  1 2 5  2 3 5  0 4 5  3 4 5

    o2 : complex of dim 2 embedded in dim 5 (printing facets)
         equidimensional, simplicial, F-vector {1, 6, 12, 8, 0, 0, 0}, Euler = 1

    i3 : fc C

    o3 = {{{}}, {x , x , x , x , x , x }, {x x , x x , x x , x x , x x , x x ,
                  0   1   2   3   4   5     0 1   0 2   1 2   0 3   2 3   0 4
         ------------------------------------------------------------------------
         x x , x x , x x , x x , x x , x x }, {x x x , x x x , x x x , x x x ,
          3 4   0 5   1 5   2 5   3 5   4 5     0 1 2   0 2 3   0 3 4   0 1 5
         ------------------------------------------------------------------------
         x x x , x x x , x x x , x x x }, {}, {}, {}}
          1 2 5   2 3 5   0 4 5   3 4 5

    o3 : List

    i4 : fc(C,1)

    o4 = {x x , x x , x x , x x , x x , x x , x x , x x , x x , x x , x x , x x }
           0 1   0 2   1 2   0 3   2 3   0 4   3 4   0 5   1 5   2 5   3 5   4 5

    o4 : List

## Ways to use fc:

- `fc(Complex)`
- `fc(Complex,ZZ)`

## For the programmer

The object fc is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/SRdeformations.m2:6157:0.