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ZZdFactorization ** Matrix -- create the tensor product of a ZZ/d-graded factorization and a map of modules

Description

For any ZZ/d-graded factorization map $C$, a map $f \colon M \to N$ of $R$-modules induces a morphism $C \otimes f$ of ZZ/d-graded factorizations from $C \otimes M$ to $C \otimes N$. This method returns this map of factorizations.

i1 : R = ZZ/101[a..d];
i2 : I = ideal(c^2-b*d, b*c-a*d, b^2-a*c)

             2                    2
o2 = ideal (c  - b*d, b*c - a*d, b  - a*c)

o2 : Ideal of R
i3 : J = ideal(I_0, I_1)

             2
o3 = ideal (c  - b*d, b*c - a*d)

o3 : Ideal of R
i4 : C = koszulMF({a,b,c,d}, a^3+b^3+c^3+d^3)

      8      8      8
o4 = R  <-- R  <-- R
                    
     0      1      0

o4 : ZZdFactorization
i5 : f = map(R^1/I, R^1/J, 1)

o5 = | 1 |

o5 : Matrix
i6 : C ** f

o6 = 0 : cokernel | c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     | <----------------------- cokernel | c2-bd bc-ad 0     0     0     0     0     0     0     0     0     0     0     0     0     0     | : 0
                  | 0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     |    | 1 0 0 0 0 0 0 0 |            | 0     0     c2-bd bc-ad 0     0     0     0     0     0     0     0     0     0     0     0     |
                  | 0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     |    | 0 1 0 0 0 0 0 0 |            | 0     0     0     0     c2-bd bc-ad 0     0     0     0     0     0     0     0     0     0     |
                  | 0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     0     0     0     |    | 0 0 1 0 0 0 0 0 |            | 0     0     0     0     0     0     c2-bd bc-ad 0     0     0     0     0     0     0     0     |
                  | 0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     |    | 0 0 0 1 0 0 0 0 |            | 0     0     0     0     0     0     0     0     c2-bd bc-ad 0     0     0     0     0     0     |
                  | 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     |    | 0 0 0 0 1 0 0 0 |            | 0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad 0     0     0     0     |
                  | 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     |    | 0 0 0 0 0 1 0 0 |            | 0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad 0     0     |
                  | 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac |    | 0 0 0 0 0 0 1 0 |            | 0     0     0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad |
                                                                                                                                                                         | 0 0 0 0 0 0 0 1 |

     1 : cokernel | c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     | <----------------------- cokernel | c2-bd bc-ad 0     0     0     0     0     0     0     0     0     0     0     0     0     0     | : 1
                  | 0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     |    | 1 0 0 0 0 0 0 0 |            | 0     0     c2-bd bc-ad 0     0     0     0     0     0     0     0     0     0     0     0     |
                  | 0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     |    | 0 1 0 0 0 0 0 0 |            | 0     0     0     0     c2-bd bc-ad 0     0     0     0     0     0     0     0     0     0     |
                  | 0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     0     0     0     |    | 0 0 1 0 0 0 0 0 |            | 0     0     0     0     0     0     c2-bd bc-ad 0     0     0     0     0     0     0     0     |
                  | 0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     0     0     0     |    | 0 0 0 1 0 0 0 0 |            | 0     0     0     0     0     0     0     0     c2-bd bc-ad 0     0     0     0     0     0     |
                  | 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     0     0     0     |    | 0 0 0 0 1 0 0 0 |            | 0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad 0     0     0     0     |
                  | 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac 0     0     0     |    | 0 0 0 0 0 1 0 0 |            | 0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad 0     0     |
                  | 0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad b2-ac |    | 0 0 0 0 0 0 1 0 |            | 0     0     0     0     0     0     0     0     0     0     0     0     0     0     c2-bd bc-ad |
                                                                                                                                                                         | 0 0 0 0 0 0 0 1 |

o6 : ZZdFactorizationMap
i7 : f ** C

o7 = 0 : cokernel | c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     0     0     0     0     | <----------------------- cokernel | c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     | : 0
                  | 0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     0     0     0     |    | 1 0 0 0 0 0 0 0 |            | 0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     |
                  | 0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     0     0     |    | 0 1 0 0 0 0 0 0 |            | 0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     |
                  | 0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     0     |    | 0 0 1 0 0 0 0 0 |            | 0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     |
                  | 0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     |    | 0 0 0 1 0 0 0 0 |            | 0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     |
                  | 0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     |    | 0 0 0 0 1 0 0 0 |            | 0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     |
                  | 0     0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     |    | 0 0 0 0 0 1 0 0 |            | 0     0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     |
                  | 0     0     0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac |    | 0 0 0 0 0 0 1 0 |            | 0     0     0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad |
                                                                                                                                                                         | 0 0 0 0 0 0 0 1 |

     1 : cokernel | c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     0     0     0     0     | <----------------------- cokernel | c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     | : 1
                  | 0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     0     0     0     |    | 1 0 0 0 0 0 0 0 |            | 0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     |
                  | 0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     0     0     |    | 0 1 0 0 0 0 0 0 |            | 0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     |
                  | 0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     0     |    | 0 0 1 0 0 0 0 0 |            | 0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     |
                  | 0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     0     |    | 0 0 0 1 0 0 0 0 |            | 0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     |
                  | 0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     0     |    | 0 0 0 0 1 0 0 0 |            | 0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     |
                  | 0     0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac 0     |    | 0 0 0 0 0 1 0 0 |            | 0     0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     |
                  | 0     0     0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad 0     0     0     0     0     0     0     b2-ac |    | 0 0 0 0 0 0 1 0 |            | 0     0     0     0     0     0     0     c2-bd 0     0     0     0     0     0     0     bc-ad |
                                                                                                                                                                         | 0 0 0 0 0 0 0 1 |

o7 : ZZdFactorizationMap
i8 : f' = random(R^2, R^{-1, -1, -1})

o8 = | 24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  |
     | 19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d |

             2      3
o8 : Matrix R  <-- R
i9 : C ** f'

          16                                                                                                                                                                                                                                                                                                                                                                                                                           24
o9 = 0 : R   <----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- R   : 0
                | 24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d |

          16                                                                                                                                                                                                                                                                                                                                                                                                                           24
     1 : R   <----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- R   : 1
                | 24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d 0               0                0                |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                24a-36b-30c-29d -8a-22b-29c-24d  34a+19b-47c-39d  |
                | 0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                0               0                0                19a+19b-10c-29d -38a-16b+39c+21d -18a-13b-43c-15d |

o9 : ZZdFactorizationMap
i10 : f' ** C

           16                                                                                                                                                                                                                                                                                                                                                                                                                           24
o10 = 0 : R   <----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- R   : 0
                 | 24a-36b-30c-29d 0               0               0               0               0               0               0               -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                0                0                0                0                |
                 | 0               24a-36b-30c-29d 0               0               0               0               0               0               0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                0                0                0                |
                 | 0               0               24a-36b-30c-29d 0               0               0               0               0               0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                0                0                |
                 | 0               0               0               24a-36b-30c-29d 0               0               0               0               0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                0                |
                 | 0               0               0               0               24a-36b-30c-29d 0               0               0               0                0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                |
                 | 0               0               0               0               0               24a-36b-30c-29d 0               0               0                0                0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                |
                 | 0               0               0               0               0               0               24a-36b-30c-29d 0               0                0                0                0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                |
                 | 0               0               0               0               0               0               0               24a-36b-30c-29d 0                0                0                0                0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  |
                 | 19a+19b-10c-29d 0               0               0               0               0               0               0               -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                0                0                0                0                |
                 | 0               19a+19b-10c-29d 0               0               0               0               0               0               0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                0                0                0                |
                 | 0               0               19a+19b-10c-29d 0               0               0               0               0               0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                0                0                |
                 | 0               0               0               19a+19b-10c-29d 0               0               0               0               0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                0                |
                 | 0               0               0               0               19a+19b-10c-29d 0               0               0               0                0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                |
                 | 0               0               0               0               0               19a+19b-10c-29d 0               0               0                0                0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                |
                 | 0               0               0               0               0               0               19a+19b-10c-29d 0               0                0                0                0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                |
                 | 0               0               0               0               0               0               0               19a+19b-10c-29d 0                0                0                0                0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d |

           16                                                                                                                                                                                                                                                                                                                                                                                                                           24
      1 : R   <----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- R   : 1
                 | 24a-36b-30c-29d 0               0               0               0               0               0               0               -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                0                0                0                0                |
                 | 0               24a-36b-30c-29d 0               0               0               0               0               0               0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                0                0                0                |
                 | 0               0               24a-36b-30c-29d 0               0               0               0               0               0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                0                0                |
                 | 0               0               0               24a-36b-30c-29d 0               0               0               0               0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                0                |
                 | 0               0               0               0               24a-36b-30c-29d 0               0               0               0                0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                0                |
                 | 0               0               0               0               0               24a-36b-30c-29d 0               0               0                0                0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                0                |
                 | 0               0               0               0               0               0               24a-36b-30c-29d 0               0                0                0                0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  0                |
                 | 0               0               0               0               0               0               0               24a-36b-30c-29d 0                0                0                0                0                0                0                -8a-22b-29c-24d  0                0                0                0                0                0                0                34a+19b-47c-39d  |
                 | 19a+19b-10c-29d 0               0               0               0               0               0               0               -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                0                0                0                0                |
                 | 0               19a+19b-10c-29d 0               0               0               0               0               0               0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                0                0                0                |
                 | 0               0               19a+19b-10c-29d 0               0               0               0               0               0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                0                0                |
                 | 0               0               0               19a+19b-10c-29d 0               0               0               0               0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                0                |
                 | 0               0               0               0               19a+19b-10c-29d 0               0               0               0                0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                0                |
                 | 0               0               0               0               0               19a+19b-10c-29d 0               0               0                0                0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                0                |
                 | 0               0               0               0               0               0               19a+19b-10c-29d 0               0                0                0                0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d 0                |
                 | 0               0               0               0               0               0               0               19a+19b-10c-29d 0                0                0                0                0                0                0                -38a-16b+39c+21d 0                0                0                0                0                0                0                -18a-13b-43c-15d |

o10 : ZZdFactorizationMap
i11 : assert isWellDefined(C ** f')
i12 : assert isWellDefined(f' ** C)

Tensoring with a factorization defines a functor from the category of $R$-modules to the category of factorizations over $R$ (that leaves the potential unchanged).

i13 : f'' = random(source f', R^{-2,-2})

o13 = {1} | -28a-47b+38c+2d  -16a+7b+15c-23d |
      {1} | 16a+22b+45c-34d  39a+43b-17c-11d |
      {1} | -48a-47b+47c+19d 48a+36b+35c+11d |

              3      2
o13 : Matrix R  <-- R
i14 : assert((C ** f') * (C ** f'') == C ** (f' * f''))
i15 : assert(C ** id_(R^{-1,-2,-3}) == id_(C ** R^{-1,-2,-3}))

See also

Ways to use this method:

  • Matrix ** ZZdFactorization
  • ZZdFactorization ** Matrix -- create the tensor product of a ZZ/d-graded factorization and a map of modules

The source of this document is in MatrixFactorizations/MatrixFactorizationsDOC.m2:3809:0.