---
name: "isofilter2"
section: "1"
platform: "linux"
package: "prover9"
version: "0.0.200911a-2.1+b2"
release: "Debian 10 (Buster)"
platforms: ["linux"]
url: "https://new.carta.tech/isofilter"
---

# isofilter2(1)

removes isomorphic structures from mace4(1) models

Part of [isofilter(1)](/isofilter/1.md).

## NAME

isofilter - removes isomorphic structures from [**mace4**(1)](/mace4/1.md) models

## SYNOPSIS

**isofilter** \[*options*\] \< *input-file* \> *output-file*\
 **isofilter0** \[*options*\] \< *input-file* \> *output-file*\
 **isofilter2** \[*options*\] \< *input-file* \> *output-file*

## DESCRIPTION

This manual page documents briefly the **isofilter**, **isofilter0** and **isofilter2** commands.

If [**mace4**(1)](/mace4/1.md) produces more than one structure, some of them are very likely to be isomorphic to others. The program **isofilter** can be used to remove isomorphic structures.

## ALGORITHM

There are multiple **isofilter** variants providing alternative algorithms.

- **isofilter**

  Uses Occurrence Profiles algorithm.

- **isofilter2**

  Uses Canonical Forms algorithm.

## OPTIONS

A summary of options is included below.

- **ignore\_constants**

  Ignore all constants during the isomorphism tests.

- **check *\<operations\>***

  Consider only the listed *operations* in the isomorphism tests.

- **output *\<operations\>***

  Output only the listed *operations*.

- **wrap**

  Enclose the resulting structures in **list(interpretations). ... end\_of\_list.**

## SEE ALSO

[**mace4**(1)](/mace4/1.md).\
 Full documentation for **isofilter** is found in the **prover9** manual, available on Debian systems in the *prover9-doc* package at */usr/share/doc/prover9-doc/manual/index.html*.

## AUTHOR

**isofilter** was written by William McCune \<mccune@cs.unm.edu\>

This manual page was written by Peter Collingbourne \<peter@pcc.me.uk\>, for the Debian project (but may be used by others).