multirow/lifting

lifting

This package contains the source code for the paper The (not so) Trivial Lifting in Two Dimensions, by Ricardo Fukasawa, Laurent Poirrier and Álinson S. Xavier.

Required Tools and Libraries

To produce the tables in the paper, the following tools and libraries were used. Different versions may produce slightly different outputs.

• GNU Make, version 3.81
• CMake, version 3.7.2
• GCC, the GNU Compiler Collection, version 6.3.0
• Ruby, version 2.4.0
• IBM® ILOG® CPLEX®, version 12.6

Build instructions

1. Navigate to the folder ../build
2. Run cmake .. followed by make lifting-benchmark.run
3. Two binaries (lifting-benchmark.run and liblifting.a) will be generated

Running the experiments

1. Build the project, following the instructions above.

2. Navigate to the folder lifting/benchmark and execute

    ./run_experiments.sh
   

3. Two CSV files will be generated inside the folder lifting/benchmark/tables, corresponding to the two tables that appear in the paper.

Modifying the instances

In order to run the experiments with a different set of instances, the file lifting/benchmark/instances/filtered/all.txt should be modified. Each line in this file describes the origin f and a lattice-free set B. The set B is described by the coordinates of its vertices. Since the benchmark code only deals with maximal lattice-free sets, it is also necessary to specify the lattice-points that belong to each facet of B. If n is the number of facets, v is an n-by-2 matrix of doubles corresponding to the vertices and l is an n-by-2 matrix of doubles corresponding to the lattice-points, then each line of the file should be written as

f[0] f[1] n v[0][0] v[0][1] ... v[n-1][0] v[n-1][1] n l[0][0] l[0][1] ... l[n-1][0] l[n-1][1]