### Final Schedule for Sage Days 38

Morning sessionswill will include talks, tutorials and open presentations.

Afternoon sessionswill be dedicated to working on the exercises from the tutorials, coding sprints, follow-up discussions, etc.

Status reports: There will be a status report every day at 17h00.

#### Monday

Morning Session:

- 08h30 : Coffee & Croissants
- 09h00 : Welcome and Introduction to Sage (source files), Sébastien Labbé
- 10h00 : Coffee Break
- 10h30 : Tour de Table and Installations, Franco Saliola
- 11h30 : Tutorial I :
Using the Sage notebook and navigating the help system, Franco Saliola

Lunch Break: 12h30 - 14h30

Afternoon Session, 14h30-17h30:

- 14h30 : Tutorial II :
Calculus and Linear Algebra in Sage- 15h30 : Coffee Break
- 16h00 : Coding Sprints
- 17h00 : Status Reports

Buffet at CRM: 17h30 - 18h30

Special event:Installation Party, 18h30After the buffet, we will continue with informal discussions, coding sprints and we will troubleshoot any problems encountered in the installations during the morning session.

#### Tuesday

Morning Session:

08h30 : Coffee & Croissants

09h00 : Øyvind Solberg,

Quivers and Path Algebras - QPA(slides and demo)

Abstract. We will give an introduction representation theory of quivers, defining quivers (directed graphs), representations of quivers and maps between representations of quivers. Further to recall basic constructions involving these objects like direct sum, kernels, special representations, etc. Representations of quivers are central for representation theory of finite dimensional algebras, and we will try to describe some of the basic problems.Next we describe the QPA project by describing the background, aims and goals, current status, design and algorithms, and main future projects.

We will end with a short demonstration of the QPA program, hopefully run via an interface developed by students at HiST/NTNU.

10h00 : Coffee Break

10h30 : Nicolas M. Thiéry,

A Sage-Combinat roadmap

Abstract.In this talk, we will present the Sage-Combinat project, whose mission is "to improve Sage as an extensible toolbox for computer exploration in (algebraic) combinatorics, and foster code sharing between researchers in this area". After a brief tour of its history and development model, we will focus on its roadmap, opening a discussion on what mid to long term goals could be, depending on interest and available work forces.11h30 : Meinolf Geck,

High performance computations around Kazhdan-Lusztig cells

Abstract.We present the computer algebra package PyCox, written entirely in Python and compatible with Sage, for computations with finite Coxeter groups and Hecke algebras. It includes some new variations of the traditional algorithms for computing Kazhdan-Lusztig cells (which now work up to type E_7) and distinguished involutions (which even work in type E_8).

Lunch Break: 12h30 - 14h30

Afternoon Session, 14h30-17h30:

- 14h30 : Tutorial III:
Programming in Python and Sage, Florent Hivert- 15h30 : Coffee Break
- 17h00 : Status Reports

#### Wednesday

Morning Session:

08h30 : Coffee & Croissants

09h00 : Derek Ruths, Introducing Zen: the Zero-Effort Network Library for Python

Abstract.This talk will introduce a new python library for network analysis and algorithmics. As datasets increase in size and algorithms demand increasing amounts of resources, it is critically important for network libraries to be efficient and performant. Few libraries available for Python (or any other platform for that matter) deliver this kind of efficiency: few can load massive network datasets or execute intensive algorithms on them. Of those that can, efficiency comes at a cost to ease of use. We don't believe that this compromise is necessary. Designed from scratch, the Zen library aims to provide the fastest, most memory efficient network routines without compromising good pythonic conventions. To date it's benchmarked network functions match or beat the fastest network libraries available in Python. In this talk, we will give a brief introduction to network analysis, discuss the design elements of Zen that make it both fast and easy-to-use, briefly overview its functionality, and discuss opportunities for integration and use with Sage.10h00 : Coffee Break

10h30 : Anne Schilling,

Markov chains for promotion operators, (Sage worksheet)

Abstract.Schuetzenberger introduced a promotion operator on arbitrary finite posets. Using a slight extension of these operators, one can define a Markov chain on all linear extensions of the poset. This generalizes the Tsetlin library which corresponds to the antichain. With Sage, we can investigate the stationary distributions and eigenvalues of the transition matrix. For rooted forests we find that the resulting monoid is R-trivial, which leads to a generalization of Brown's theory of Markov chains for left regular bands. This is based on mathematical explorations with Arvind Ayyer and Steven Klee, and the patch Trac 12536 with Nicolas Thiery.11h00 : Viviane Pons,

Bases of multivariate polynomials, (Sage worksheet)

Abstract.We have developed a patch in sage to consider multivariate polynomials as formal sums of vectors. Each vector corresponds to the exponent of a monomial. From simple operations on vectors, we obtain operations on the polynomials. We define thedivided differencesand we explain how they can be used to generate linear bases of the ring of multivariate polynomials. We show that they can be seen as a generalization of the Schur basis of symmetric polynomials.11h30 : Tutorial IV:

Contributing to Sage, Anne Schilling

Lunch Break: 12h30 - 14h30

Afternoon Session, 14h30-17h30: exercises and coding sprints with coffee break and status reports

- 15h30 : Coffee Break
- 17h00 : Status Reports

#### Thursday

Morning Session:

- 08h30 : Coffee & Croissants
- 09h00 : Open Presentations
- 10h00 : Coffee Break
- 10h30 : Open Presentations
- 11h30 : Tutorial V:
Cython, Florent Hivert

Lunch Break: 12h30 - 14h30

Afternoon Session, 14h30-17h30: exercises and coding sprints with coffee break and status reports

- 15h30 : Coffee Break
- 17h00 : Status Reports

#### Friday

Morning Session:

- 08h30 : Coffee & Croissants
- 09h00 : Open Presentations
- 10h00 : Coffee Break
- 10h30 : Open Presentations

Lunch Break: 11h30 - 13h30

- 13h30 : Doron Zeilberger: n
^{n-2}

Afternoon Session, 14h30-17h30: exercises and coding sprints with coffee break and status reports

- 15h30 : Coffee Break
- 17h00 : Status Reports

### Open Presentations

Open presentations are quick (5 to 15 minutes) presentations done by the participants. It can be demonstrations of projects done during the week. Or it can be about anything of interest to the participants including software useful for teaching or research.

Thursday :

- Using sagetex to generate of math homeworks, by Nicolas Thiéry (zip file with example)

interact demo, by Mélodie

animate demo, by Michael

Friday :

- sagetex Tutorial, by Pierre Cagne
- WebWorK and Sage integration, by Malcolm
- Tutorial V:
*Cython Part 2*, by Florent Hivert - Python Coding Convention, by Sébastien Labbé

Not done yet :

- a demo of the new IPython 0.12 Notebook, by Pierre Cagne
- What's new with Python 2.7 recently included into Sage?, by ???
- some interact made by Florent
- pgfplots + gnuplot, by Alexandre Blondin Massé
- tikz2pdf, by Sébastien Labbé