Sage Days 114
Following the 34th FPSAC 2022.
The Sage days will consist in an intense threeday meeting at IMSc:
July 25–27, 2022, The Institute of Mathematical Sciences (IMSc), Chennai, India
Zoom link: https://zoom.us/j/96302249436, Meeting ID: 963 0224 9436, Passcode: 932291
Recordings on youtube (unfortunately, some are missing the first few minutes:) Martin Rubey, Combinatorial Species, Eric Marberg, Shifted combinatorial Hopf algebras for Ktheory, Julian Rüth, Interactive Widgets in SageMath, Alba Málaga, 3D printing mathematical surfaces, Ajit Kumar, An introduction to SageMath; Samuel Lelièvre, SageMath for the educator (starting around 1:04:00)
Following this intense period, a working group on software for mathematics and their illustration will meet twice a week for a few weeks, mostly at the Chennai Mathematical Institute (CMI), led by Julian Rüth and Samuel Lelièvre.
Organizing Committee
 Arvind Ayyer (Indian Institute of Science)
 Manoj Kummini (Chennai Mathematical Institute)
 Samuel Lelièvre (Laboratoire de mathématique d'Orsay, Université ParisSaclay)
 Julian Rüth
 Amritanshu Prasad (The Institute of Mathematical Sciences, Chennai)
 Travis Scrimshaw (Hokkaido University)
 S. Viswanath (The Institute of Mathematical Sciences, Chennai)
 Pascal Weil (CNRS, Chennai/Bordeaux)
Tentative Schedule
Day 1: 25th July 2022
Time 
Speaker 
Title 
09301030 
Ajit Kumar 
Introduction to SageMath 
10301130 
Samuel Lelièvre 
SageMath for Educators 
11301200 
High Tea 

12001300 
"Bring Your Own Problem" Session 

13001430 
Lunch 

14301530 
Julian Rüth 
SageMath Installation 
15301630 
Projects for Coding Sprints 

16301730 
Coding Sprints 
Day 2: 26th July 2022
Time 
Speaker 
Title 
09001000 
Alba Málaga 
3D printing mathematical surfaces 
10001030 
Coffee Break 

10301145 
The Organizers (mostly) 
Tutorials Upon Request 
11451245 
Julian Rüth 
Interactive Visualization in SageMath 
12451415 
Lunch 

14151730 
Coding Sprints 
Day 3: 27th July 2022
Time 
Speaker 
Title 
09001000 
Eric Marberg 
Shifted combinatorial Hopf algebras for Ktheory 
10001030 
Coffee Break 

10301130 
Martin Rubey 
Combinatorial Species 
11451245 
Kanak Dhotre 
Visualizing Julia Sets 
12451415 
Lunch 

14151730 
Coding Sprints 
Talk Details
Ajit Kumar: An introduction to SageMath Slides
Eric Marberg: Shifted combinatorial Hopf algebras for Ktheory slides
The selfdual Hopf algebra of symmetric functions Sym embeds into the quasisymmetric functions QSym. The dual of QSym is the Hopf algebra of noncommutative symmetric functions NSym, which itself embeds into the selfdual MalvenutoReutenaurer Hopf algebra of permutations. These embeddings and their adjoint projections can be conveniently drawn as a diagram of six Hopf algebras. This talk will discuss "Ktheoretic" and "shifted" generalizations of this diagram, along with some algorithmic problems related to computing products, coproducts, and antipodes in the relevant Hopf algebras. The new results in this talk are joint work with Joel Lewis.
Alba Málaga: 3D printing mathematical surfaces Slides
As a mathematician, you don't need to touch a surface to feel how beautiful it is. But what if you want to talk about it to your grandpa or your least mathematical friend? There is somethng deeply satisfying about being able to hand them an object which represents the concept you want to talk about pretty well and which they can touch. The methods and challenges will vary according to which mathematical object you try to represent. In this talk, I will present cookbook methods and discuss challenges for 3Dprinting three very classical kinds of mathematical surfaces: constantnegative curvature surfaces, minimal surfaces, algebraic surfaces. The software used will be Sagemath, MathMod, Surface Evolver, Blender and Cura.
Julian Rüth: Interactive Visualization in SageMath
We look at existing visualization in SageMath and that it's mostly lacking real interactivity. Interactive widgets are, however, not so hard to build with SageMath. We showcase the ipymuvue package which is a reimplementation of ipyvue in Vue3.
The graph editor developed during the talk is at https://github.com/flatsurf/ipymuvue/tree/master/examples/.
The slides from the talk are at https://gist.github.com/saraedum/2cd063e97f555c13816439ffdcb87af8
Sage Club at CMI
Following the Sage Days, a ''Sage Club'' will meet twice a week at CMI. The Sage Club is going to be an open forum, led by Samuel Lelièvre and Julian Rüth, where we will learn more about SageMath, focusing on the interests of the participants. Just as with the Sage Days, beginners and students are very welcome at any session.