Coding sprints for [Free and Practical Software for Algebraic Combinatorics 2019](https://wiki.sagemath.org/fpsac19)

--- tags: OpenDreamKit, FPSAC, Sage, GAP, workshop --- # Coding sprints for [Free and Practical Software for Algebraic Combinatorics 2019](https://wiki.sagemath.org/fpsac19) ## Status reports & Testimonials See [trac tickets with fpsac2019 keyword](https://trac.sagemath.org/query?status=closed&status=needs_info&status=needs_review&status=needs_work&status=new&status=positive_review&keywords=~fpsac2019&order=priority). * Many beginners got their first experiences with the sage development process. The tutorials and exercises helped a lot to get started and to gain confidence with git, git trac, sage development, ... * The official talks showed the participants how to use free and practical software for their own research. * The diversity of the group allowed us to work on many different projects and learn from each other. * Trying to resurrect Viviane's code for multivariate polynomials. * Finalization of symmetric functions tutorial * Integration of a linear time algorithm for enumeration of all distinct squares in a word [#28182](https://trac.sagemath.org/ticket/28182) (pending review) and [#23573](https://trac.sagemath.org/ticket/23573). * For future organisers: Providing good network connection is hard. Eduroam alone is not enough to provide stable connections. Think about backup solutions. ## Hopf algebras ### Hopf and other superalgebras as their own hierarchy (#25603) Travis Scrimshaw, Darij Grinberg, Nicolas Thiéry ... Sprint tonight 20:30 A, B, C: Super algebras tensor([A, B, C]) -> SuperAlgebras().SignedTensorProducts() tensor([A, B, C], category=Algebras()) SuperAlgebras() subcategory of Algebras().Graded() SuperAlgebras().TensorProducts() subcategory of Algebras().Graded().TensorProducts() C -> C.default_tensor_construction Modules().SubcategoryMethods.tensor = tensor SuperAlgebras().SubcategoryMethods.tensor -> signed_tensor tensor([A,B,C]) -> find the meet category D, and build D._tensor_([A,B,C]) Enable A.tensor(B,C) ??? SuperAlgebras().SignedTensorProducts() is a subcategory of Modules().Graded().TensorProducts() ## Combinatorics ### RSK reviewing (#27852), coRSK (#25070). Darij Grinberg, Anne Schilling, Travis ... https://github.com/darijgr/sage-subspace/ ### [Semistandard Multiset Tableaux and Crystal on Semistandard Set Valued Tableaux (#28134)](https://trac.sagemath.org/ticket/28134) Wencin Poh, Jeremy Meza, Anne Schilling, Kyle Meyer ... Sprint at 20:00 ### Oriented Matroids Aram Dermenjian Created an (alpha) package for oriented matroids. https://github.com/thecaligarmo/oriented_matroids/ ### Framework for finite dynamics Darij Grinberg, Tom Roby, reviewed by Travis Scrimshaw was finished off during these SageDays https://trac.sagemath.org/ticket/24128 ## Visualization of combinatorial objects Henri, Abolape ### Using and extending Sage-Combinat-Widgets Abolape Explore the use of [sage-combinat-widgets](https://github.com/sagemath/sage-combinat-widgets/) for teaching and research purposes. E.g. implement a Robinson-Shensted App Presenter: Odile Bénassy + ... Installation: Mee Seong, Harrison sage -pip install sage_combinat_widgets Workshop Tuesday from 10:30 and from 15:30 -- room **202** #### Polyominos by Henri D -> 1 PR accepted, 2 will be accepted #### Packed words by Hugo M -> work in progress #### Creating paths between widget cells by Can OO -> work to be started ## Symbolic Computation ### Differential-difference algebra Getting a more _natural_ implementation for differential rings in a general way, adapting the strucre to general rings, fields and the coercion system in Sage. Or just learn with precision how it is already in Sage. Antonio, Mee Seong ## Documentation and tutorial ### Symmetric function tutorial Merge the [new symmetric function tutorial](https://github.com/sagemath/more-sagemath-tutorials/blob/master/tutorial-symmetric-functions.rst) into SageMath Pauline Hubert, Anne Schilling? ### Polish the [Start here](https://github.com/sagemath/more-sagemath-tutorials/blob/master/tutorial-start-here.rst) tutorial and merge it into SageMath? Nicolas, Antonio,... ### Review [More SageMath Tutorials](https://more-sagemath-tutorials.readthedocs.io/) and see what could be merged into SageMath Nicolas, Antonio, Mee Seong,... ### Dynamical Algebraic Combinatorics Tutorial Tom Roby (creating rst files, just getting started) ## Subspaces Darij Grinberg, Nicolas T. ## Parallelization Pauline (problem solved !), Tomer (Improve zetalib) ## KLR-algebras? ## Type q(n+1)-crystal structure on Shifted Prime Tableaux Basically define f_{-1} operator on set of shifted prime tableaux and its tensor product rule Wencin Poh, Eric Marberg?, Ines Rodrigues ## King Symplectic Tableaux and Sheats Bijection (#26143) Implement a SymplecticTableau object for Kashiwara-Nakashima tableaux and King tableaux that doesn't go through (slow) crystal algorithms. There is already a ticket, but it's colored red so I think that means something is very wrong... Jeremy Meza, João Santos ## Package dd_functions Steps: - [ ] make it available on a public repo - [x] make it a Python package (see the setup.py of https://github.com/sagemath/sage_sample) - [x] Add a demo notebook - [ ] Add Binder configuration (see the Dockerfile of sage_sample) + binder link/badge from the README - [ ] Publish on pipy - [x] Configure sphinx for the documentation - [ ] More tests and documentation - [ ] Write a tutorial - [ ] Setup continuous integration (see sage_sample) - [ ] ? Merge into SageMath Do you want to help? Contact me (Antonio Jimenez-Pastor) ## Package [zetalib](https://pypi.org/project/zetalib/) Python 3 compatibility and a little improvement to logging. We should add a demo notebook with Binder support. ## Add number of subgroups method to AbelianGroup See [trac #28136](https://trac.sagemath.org/ticket/28136) for future addition of number_of_subgroups(). Ready for review! On the way we discovered bugs for simple things in subgroups of a subgroup of an abelian group. See [trac #28150](https://trac.sagemath.org/ticket/28150) for details. Tomer ## Add a function that gives the complementary of a subword See [trac #28160](https://trac.sagemath.org/ticket/28160) for details. The ticket has a positive review and will soon be closed. Here are some examples that I got running the algorithm on French and English dictionaries. ### French albatros bars alto ambiance banc amie banlieues bleue anis botaniste tante bois botaniste botte anis céramiques émis craque craignent crin agent criminel miel crin doctrine dote crin versatile veste rail voitures ours vite ### English greatest rest gate vertices vets rice violates vile oats facility fail city threaten then rate ## Add yours!

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