---
name: "nauty-planarg"
section: "1"
platform: "linux"
package: "nauty"
version: "2.8.9+ds-1+b1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/nauty-planarg"
---

# nauty-planarg(1)

test graphs for planarity and find embeddings or obstructions

## NAME

nauty-planarg - test graphs for planarity and find embeddings or obstructions

## SYNOPSIS

**planarg** \[*-v*\] \[*-nVq*\] \[*-p\|-u*\] \[*infile* \[*outfile*\]\]

## DESCRIPTION

-

  For each input, write to output if planar.

-

  The output file has a header if and only if the input file does.

- **-v**

  Write non-planar graphs instead of planar graphs

- **-V**

  Write report on every input

- **-u**

  Don't write anything, just count

- **-p**

  Write in planar\_code if planar (without **-p**, same format as input)

- **-P**

  Like **-p** but big-endian (same for \<= 255 vertices)

- **-k**

  Follow each non-planar output with an obstruction in sparse6 format (implies **-v**, incompatible with **-p**)

- **-n**

  Suppress checking of the result

- **-q**

  Suppress auxiliary information

-

  This program permits multiple edges and loops