Mohamed Barakat

improved/fixed CAP_INTERNAL_CONSTRUCTIVE_CATEGORIES_RECORD.IsAbelianCategory

1

resolves https://github.com/homalg-project/CAP_project/issues/1473

LiftAlongMonomorphism/ColiftAlongEpimorphism

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The ability to compute `LiftAlongMonomorphism`/`ColiftAlongEpimorphism` is currently used to distinguish pre-abelian categories from abelian ones. However, in `CAP` they can be [derived from the set-theoretic operations `Lift`](https://github.com/homalg-project/CAP_project/blob/973f3af1b0548ae5c1dfdbbbd86b6aa925afac30/CAP/gap/DerivedMethods.gi#L1191-L1201)/`Colift` *with no further...

Derive limit instead of colimit operations

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I suggest deriving the limit from the colimit operations rather than vice versa. At some point, we can derive most colimit operations from the towers and have less code to...

Make use of the opposite category to automatically generate code for opposite derivations

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As discussed with Fabian it would be desirable to write half of the derivations and automatically generate the opposite versions using `CompilerForCAP` and the current infrastructure. Background: I have written...

Broken if-statement

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The condition in this if-statement https://github.com/homalg-project/CAP_project/blob/039bfd462710bd481024c1b501ad9681e6160c09/CompilerForCAP/gap/InferDataTypes.gi#L645 should include `and not data_type = "list_with_unknown_element_type"`.

I suggest renaming `AdditiveClosure` into `StrictAdditiveClosure` since its universal property only works for functors into strict additive categories (those for which the unitors and associators of the direct sums are...

Remove IsCongruentForMorphisms from the record entry EveryCategory

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I suggest removing `IsCongruentForMorphisms` from `CAP_INTERNAL_CONSTRUCTIVE_CATEGORIES_RECORD.EveryCategory` and adding it to a new record entry of `CAP_INTERNAL_CONSTRUCTIVE_CATEGORIES_RECORD`. I can think of two possible names for this algorithmic property: * `IsCategoryWithDecidableEqualityOfMorphisms` *...

installed derivations for Abelian categories

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* IsomorphismFromKernelOfCokernelToImageObject * IsomorphismFromCoimageToCokernelOfKernel

Extending the range of a homomorphism structure of a category instance multiple times signals an error

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```gap gap> LoadPackage("FunctorCategories"); true gap> FiniteStrictCoproductCocompletion( FinBouquets ); FiniteStrictCoproductCocompletion( FinBouquets ) gap> FiniteStrictCoproductCocompletion( ModelingCategory( FinBouquets ) ); Error, there is already a method known for DistinguishedObjectOfHomomorphismStructureExtendedByFullEmbedding with a category filter...