# sympol - Man Page

symmetric polyhedra tool

## Synopsis

**sympol** [Options] [*INPUT_FILE*]

## Description

SymPol computes restricted automorphisms of polyhedra and performs polyhedral description conversion up to a given or computed symmetry group.

SymPol mostly uses the .ine/.ext file format used by cddlib and lrslib; (http://cgm.cs.mcgill.ca/~avis/C/lrslib/USERGUIDE.html#File%20Formats). However, unlike cddlib, SymPol requires that every inequality (H-representation) or vertex and ray (V-representation) occupy a single line. In addition, SymPol offers an extension to the format

The extension permits the inclusion of the automorphism group of a polyhedron, or parts of it, in the file. It is given after the end of the H- or V-representation of a permutation group, as follows.

permutation group

p

{ list of #p group generators }

q

{ #q base points separated by whitespace }

The *p* group generators are to be given in cycle form, where commas separate cycles. The value *q* may be set to zero if no base of the group is known.

## Options

- -h, --help
Show a help message.

- -v, --verbose[=
*N*] Set the verbosity level, 0 by default. If

*N*is omitted, 1 is assumed.- -t, --time
Enable time measurement.

- -i, --input-file
*FILE* Read an input file (.ine or .ext). The file can also be listed last on the command line.

- --automorphisms-only
Compute only restricted automorphisms and then exit.

- --no-automorphisms
Ignores the given symmetry group and does not attempt to compute restricted automorphisms.

- --bliss
Use bliss graph automorphism tool to compute restricted automorphisms (default if bliss is available).

- --permlibmatrix
Use PermLib matrix automorphism search to compute restricted automorphisms.

- --eigen
Use floating point arithmetic based on Eigen to compute restricted automorphisms.

- -e, --estimation-only
Compute only LRS estimation and then exit.

- -d, --direct
Compute dual description directly.

- -a, --adm
Use one level of adjacency decomposition, solve subproblems directly.

- --idm-adm-level
*idm-level adm-level* Use a combined IDM/ADM strategy with the indicated levels.

- --adm-idm-level
*adm-level idm-level* Use a combined ADM/IDM strategy with the indicated levels.

- --adm-estimate
*threshold* Use adjacency decomposition method up to the given estimate threshold.

- --adm-dim
*threshold* Use adjacency decomposition method up to the given dimension threshold.

- --adm-incidence
*threshold* Use adjacency decomposition method up to the given incidence number threshold.

- --idm-adm
*idm-threshold adm-threshold* Use a combined IDM/ADM strategy with the indicated thresholds.

- --cdd
Use cdd for core dual description conversion (EXPERIMENTAL).

- --adjacencies
Record facet adjaencies. Requires ADM method at level 0.

## Parameters

- --conf-lrs-estimates=
*N* The number of estimates that LRS performs (default: 8).

- --conf-lrs-estimate-maxdepth=
*N* The maximal allowed depth of LRS estimates (default: 3).

- --conf-compute-invariants=
*N* The maximal degree of permutation group invariant polynomials to use (default: 0).

- --conf-compute-orbit-limit=
*N* Memory limit in megabytes for computing the full orbit (default: 1024).

- --conf-compute-canonical-representatives=
*N* Nonzero to compute canonical representatives for faces (default: 0).

- --conf-intermediate-poly-fileprefix=
*PREFIX* Prefix for filenames in which intermediate polyhedra are saved. This is useful for debugging and analyzing instances. Default: empty prefix.