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id _ ZZdFactorization -- the identity map of a ZZ/d-graded factorization

Description

The collection of ZZ/d-graded factorizations together with ZZ/d-graded factorization morphisms forms a category. In particular, every ZZ/d-graded factorization has an identity map.

i1 : S = ZZ/101[a,b,c]

o1 = S

o1 : PolynomialRing
i2 : R = S/(a^2+b^2+c^2);
i3 : m = ideal vars R

o3 = ideal (a, b, c)

o3 : Ideal of R
i4 : C = tailMF m

      4      4      4
o4 = S  <-- S  <-- S
                    
     0      1      0

o4 : ZZdFactorization
i5 : D = tailMF (m^2)

      8      8      8
o5 = S  <-- S  <-- S
                    
     0      1      0

o5 : ZZdFactorization
i6 : f = id_C

          4                       4
o6 = 0 : S  <------------------- S  : 0
               {3} | 1 0 0 0 |
               {3} | 0 1 0 0 |
               {3} | 0 0 1 0 |
               {3} | 0 0 0 1 |

          4                       4
     1 : S  <------------------- S  : 1
               {4} | 1 0 0 0 |
               {4} | 0 1 0 0 |
               {4} | 0 0 1 0 |
               {4} | 0 0 0 1 |

o6 : ZZdFactorizationMap
i7 : assert isWellDefined f
i8 : assert isFactorizationMorphism f
i9 : g = id_D

          8                               8
o9 = 0 : S  <--------------------------- S  : 0
               {4} | 1 0 0 0 0 0 0 0 |
               {4} | 0 1 0 0 0 0 0 0 |
               {4} | 0 0 1 0 0 0 0 0 |
               {4} | 0 0 0 1 0 0 0 0 |
               {4} | 0 0 0 0 1 0 0 0 |
               {4} | 0 0 0 0 0 1 0 0 |
               {4} | 0 0 0 0 0 0 1 0 |
               {4} | 0 0 0 0 0 0 0 1 |

          8                               8
     1 : S  <--------------------------- S  : 1
               {5} | 1 0 0 0 0 0 0 0 |
               {5} | 0 1 0 0 0 0 0 0 |
               {5} | 0 0 1 0 0 0 0 0 |
               {5} | 0 0 0 1 0 0 0 0 |
               {5} | 0 0 0 0 1 0 0 0 |
               {5} | 0 0 0 0 0 1 0 0 |
               {5} | 0 0 0 0 0 0 1 0 |
               {5} | 0 0 0 0 0 0 0 1 |

o9 : ZZdFactorizationMap
i10 : assert isWellDefined g
i11 : assert isFactorizationMorphism g

See also

Ways to use this method:


The source of this document is in MatrixFactorizations/MatrixFactorizationsDOC.m2:2712:0.