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# coordinates -- The coordinates of a face.

## Synopsis

• Usage:
coordinates(C)
• Inputs:
• Outputs:

## Description

Returns the coordinates of a face if some coker graded ring can be associated to F (if there is non one can give the second argument C).

 i1 : R=QQ[x_0..x_4] o1 = R o1 : PolynomialRing i2 : addCokerGrading R o2 = | -1 -1 -1 -1 | | 1 0 0 0 | | 0 1 0 0 | | 0 0 1 0 | | 0 0 0 1 | 5 4 o2 : Matrix ZZ <--- ZZ i3 : C=simplex R o3 = 4: x x x x x 0 1 2 3 4 o3 : complex of dim 4 embedded in dim 4 (printing facets) equidimensional, simplicial, F-vector {1, 5, 10, 10, 5, 1}, Euler = 0 i4 : bC=boundaryOfPolytope C o4 = 3: x x x x x x x x x x x x x x x x x x x x 0 1 2 3 0 1 2 4 0 1 3 4 0 2 3 4 1 2 3 4 o4 : complex of dim 3 embedded in dim 4 (printing facets) equidimensional, simplicial, F-vector {1, 5, 10, 10, 5, 0}, Euler = -1 i5 : F=bC.fc_2_0 o5 = x x x 0 1 2 o5 : face with 3 vertices i6 : coordinates F o6 = {{-1, -1, -1, -1}, {1, 0, 0, 0}, {0, 1, 0, 0}} o6 : List