---
name: "mord"
section: "1"
platform: "linux"
package: "scotch"
version: "7.0.17-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/mord"
---

# mord(1)

compute sparse matrix orderings of meshes

## NAME

**mord** - compute sparse matrix orderings of meshes

## SYNOPSIS

```
mord [options] [mfile] [ofile] [lfile]
```

## DESCRIPTION

**The mord program computes, in a sequential way, an ordering of a** **Scotch source mesh representing the pattern of some symmetric sparse** **matrix. Only nodes of the mesh are effectively ordered. Elements** **provide connectivity information, such that every node is considered** **to be linked to all of the nodes which share at least an element** **with it.**

**Source mesh file** *mfile* **can only be a centralized mesh file. The** **resulting ordering is stored in file** *ofile***. Eventual logging** **information (such as the one produced by option -v) is sent to file** *lfile***. When file names are not specified, data is read from standard** **input and written to standard output. Standard streams can also be** **explicitely represented by a dash '-'.**

**When the proper libraries have been included at compile time, gord** **can directly handle compressed meshes, both as input and output. A** **stream is treated as compressed whenever its name is postfixed with** **a compressed file extension, such as in 'brol.msh.bz2' or '-.gz'. The** **compression formats which can be supported are the bzip2 format** **('.bz2'), the gzip format ('.gz'), and the lzma format ('.lzma').**

## OPTIONS

- **-copt**

  **Choose default ordering strategy according to one or** **several** *options* **among:**

  - **b**

    **enforce load balance as much as possible.**

  - **q**

    **privilege quality over speed (default).**

  - **s**

    **privilege speed over quality.**

  - **t**

    **enforce safety.**

- **-h**

  **Display some help.**

- **-m*mfile***

  **Save column block mapping data to file** *mfile***. Mapping data** **specifies, for each node vertex, the index of the column** **block to which this node vertex belongs.**

- **-o*strat***

  **Use sequential mesh ordering strategy** *strat* **(see** **Scotch user's manual for more information).**

- **-t*tfile***

  **Save partitioning tree data to file** *tfile***. Partitioning** **tree data specifies, for each node vertex, the index of the** **first node vertex of the parent block of the block to which** **the node vertex belongs. Altogether with the mapping data** **provided in file** *mfile***, it allows one to rebuild the** **separator tree of the nested dissection process.**

- **-V**

  **Display program version and copyright.**

- **-v*verb***

  **Set verbose mode to** *verb***. It is a set of one of more** **characters which can be:**

  - **s**

    **strategy information.**

  - **t**

    **timing information.**

## EXAMPLE

**Reorder matrix mesh brol.msh and save the resulting ordering to** **file brol.ord using the default sequential mesh ordering strategy:**

```
    $ mord brol.msh brol.ord
```

## SEE ALSO

**[gmk\_msh(1)](/gmk_msh/1.md), [gotst(1)](/gotst/1.md), [mtst(1)](/mtst/1.md).**

**Scotch user's manual.**

## AUTHOR

**Francois Pellegrini \<francois.pellegrini@labri.fr\>**