next | previous | forward | backward | up | top | index | toc | Macaulay2 website
SRdeformations :: addFacetDataToComplex

addFacetDataToComplex -- Adds to a complex facet data.

Synopsis

Description

Adds to a complex the facet data, i.e., C.facets, C.dim, C.fvector, C.isEquidimensional, C.isSimp are updated.

This allows us to add the facet data later to a complex generated previously by newEmptyComplex.

Note that the input C is modified by this method.

This function is mainly used internally, but may occasionally be useful to the user and is hence exported.

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

o4 : complex of dim 1 embedded in dim 4 (printing facets)
     equidimensional, simplicial, F-vector {1, 5, 5, 0, 0, 0}, Euler = -1
i5 : Cl=newEmptyComplex(R)

o5 = empty complex

o5 : complex of dim -1 embedded in dim 4 (printing facets)
     equidimensional, simplicial
i6 : addFacetDataToComplex(Cl,facets C)

o6 = done
i7 : Cl==C

o7 = true

See also

Ways to use addFacetDataToComplex :

For the programmer

The object addFacetDataToComplex is a method function.