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--- workshops:workshop0125 [2025/01/08 10:34] – Add speaker, remove organizer lkastner
+++ workshops:workshop0125 [2025/01/24 10:18] (current) – [polymake conference] weis
@@ Line 16: / Line 16: @@
 Please fill out the [[workshops:workshop0125:registration|registration form]]!
-===Preliminary Schedule===
+===Schedule===
 <HTML><div style="width: 100%;"><div style="float: left; padding-right: 10px; width: 800px;"></HTML>
 ^ **Friday**   ^                                                                                                                   ||
 | 09:00-09:30  | **Registration**                                                    |                                      ||
-| 09:30-10:30  | **Talk: TBA **    |                                                         ||
+| 09:30-10:30  | **Talk: Polyhedral Computations using Linear Optimization Oracles **                                                             ||
-| :::          | // Marc Pfetsch //                                                        |                                    ||
+| :::          | // [[https://www2.mathematik.tu-darmstadt.de/~pfetsch/index.en.html|Marc Pfetsch]] //                                                                                            ||
 | 10:30-11:00  | **Break and Helpdesk**                                                                                   ||
-| 11:00-12:00  | **Tut: TBA ** E-N 058                           | **Tut: TBA** E-N 057  ||
+| 11:00-12:00  | **Tut: polymake basics ** E-N 058                           | **Tut: Oscar-polymake Tips and Tricks** E-N 057  ||
-| :::          | // TBA //                                   | //TBA// ||
+| :::          | // [[https://page.math.tu-berlin.de/~makhlin/|Igor Makhlin]]  //                                   | // [[https://antonydellavecchia.github.io/|Antony Della Vecchia]] // ||
 | 12:00-14:00  | **Lunch and Coffee**                                 ||
-| 14:00-15:00  | **Tut: TBA**                            | **Tut: TBA**     |
+| 14:00-15:00  | **Tut: application tropical** E-N 058                 | **Tut: Matroids in Polymake and Oscar**  E-N 057   |
-| :::          | // TBA //                                | // TBA //               |
+| :::          | // [[https://page.math.tu-berlin.de/~weis/|Lena Weis]] //                                | //[[https://page.math.tu-berlin.de/~wack/|Marcel Wack]] & [[https://sites.google.com/view/dantelubermath/home|Dante Luber]] //              |
 | 15:00-15:30  | **Break and Helpdesk**                                                                                   ||
-| 15:30-16:30  | ** TBA ** ||
+| 15:30-16:30  | ** Use cases ** ||
+|   | ** Exploring polytropes through secondary fans ** ||
+|   | // [[https://kafe.dev/|Kamillo Ferry]] // ||
+|   | ** Algebraic shifting ** ||
+|   | // [[https://page.math.tu-berlin.de/~lenzen/|Fabian Lenzen]] // ||
 | 16:30-18:15  | **Helpdesk**                                                                                             ||
 | ~18:45       | **Dinner** (self paid, at [[http://cafe-hardenberg.com/|Café Hardenberg]])                                        ||
@@ Line 36: / Line 40: @@
 === Abstracts ===
-TBA
+== Marc Pfetsch: Polyhedral Computations using Linear Optimization Oracles ==
+This talk will cover two topics in which polyhedral computations are
+based on an indirect access to the underlying polyhedron via an oracle
+that can solve linear optimization problems. In both cases, the oracle
+is given by the (computationally expensive) solution of a mixed-integer
+linear optimization problem.
+The first topic deals with the computation of so-called local cuts.
+These are inequalities that can be added during a branch-and-cut
+algorithm to solve mixed-integer linear problems. The idea is to
+generate these inequalities by using small (local) subproblems for which
+the oracle is reasonably fast in practice. The inequalities can be
+constructed using a so-called Frank-Wolfe algorithm, which computes a
+projection onto the polyhedron.
+The second topic is about sensitivity analysis of mixed-integer linear
+optimization problems. We would like to compute the normal cone at a
+particular vertex. Since the polyhedron is not directly accessible, an
+algorithm that iteratively builds the cone is designed. In each main
+iteration the cone is possibly extended by a ray that is computed using
+the oracle and a beneath-and-beyond step is performed.
+== Igor Makhlin: polymake basics ==
+In this tutorial, we will see some basic computations to get acquainted with polymake objects. Download Jupyter notebook [[https://polymake.org/lib/exe/fetch.php/workshops/polymake_basics_2025.ipynb|here]].
+== Antony Della Vecchia & Benjamin Lorenz ==
+An interactive session exposing some of the glue between Oscar and polymake.
+== Lena Weis ==
+An interactive session introducing tropical computations in polymake. The notebook can be found {{ :workshops:tropical.ipynb |here}}.
+== Marcel Wack & Dante Luber ==
+An interactive session exploring all things matroid in polymake and Oscar.
+==Kamillo Ferry: Exploring polytropes through secondary fans==
+Polytropes are a special class of polyhedra with applications to optimization and statistics.
+We explore the combinatorics of polytropes using secondary fans of special point configurations.
 =====Hotel recommendations in proximity of the Institute of Mathematics:=====
@@ Line 51: / Line 97: @@
 ===== Local organizers =====
-  - [[https://page.math.tu-berlin.de/~wack/|Marcel Wack]]
   - [[https://page.math.tu-berlin.de/~weis/|Lena Weis]]
 Please contact us with any questions about the workshop. To email us, please use ''LASTNAME@math.tu-berlin.de''.