Fifteen numerical models
Class: BIP · ILP · MILP · Scripts: one per model,
python/ex01_van.py … python/ex15_timetable.py
The fifteen numerical models of the course, from EX 1 to EX 15. Explicit data, few variables, one technique per model: they are the easiest ones, and they come before the three families of problems and the mixed problems.
Every numerical model always has the same five parts:
- the statement, with the data of the instance;
- the variables, with their domain and their count;
- the model of the instance, primal and dual;
- a feasible solution built by hand, which gives the primal bound;
- a dual solution built by hand, which gives the dual bound, and the comparison with the solver's optimum.
Every model has its own page, its own script and its own notebook.
| Model | What it brings into play | Notebook |
|---|---|---|
| EX 1 — The eight-seat van | selection with a capacity and an implication between groups | |
| EX 2 — Bus lines | assignment with a capacity in number of lines | |
| EX 3 — Relay | assignment with more resources than tasks; totally unimodular matrix | |
| EX 4 — Hub-and-spoke | covering: the minimum number of hubs | |
| EX 5 — Mutual funds bought in lots | integer counts in lots, with a proportion constraint | |
| EX 6 — Vehicles with a minimum quantity | minimum lot: a minimum quantity if the type is produced | |
| EX 7 — Custom aircraft with a fixed set-up cost | fixed set-up cost and a free quantity up to the order | |
| EX 8 — Seminars | exact cardinality, non-adjacency, dual with a free variable | |
| EX 9 — Queens on the chessboard | packing on a chessboard: rows, columns and diagonals | |
| EX 10 — Tools of a CNC machine | selection with a tool set: disaggregated activation | |
| EX 11 — Shoes with a minimum production threshold | minimum lot with three shared resources | |
| EX 12 — Balancing between two workers | min-max against difference: same solutions, different values | |
| EX 13 — Emergency department shifts | covering the daily requirements with weekly shifts | |
| EX 14 — Shoes: production, inventory and hirings | inventory balance and workforce over three months | |
| EX 15 — The music school timetable | conflicts, non-adjacency and preferences to avoid |