# sympol man page

sympol — 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/…). 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.