---
name: "cs_preprocess"
section: "1"
platform: "linux"
package: "ecs"
version: "2.0.0.rc1-3"
release: "Debian 6.0 (Squeeze)"
platforms: ["linux"]
url: "https://new.carta.tech/cs_preprocess"
---

# cs\_preprocess(1)

Code\_Saturne preprocessor

## NAME

cs\_preprocess - Code\_Saturne preprocessor

## SYNOPSIS

**cs\_preprocess** -m \<file\> \[-sc\] \[options\]\

## DESCRIPTION

Code\_Saturne preprocessor reads meshes from several formats. It enables non-conforming joining and periodicity handling, as well as some postprocessing for mesh checking.

## OPTIONS

- \-m, --mesh \<file\>

  **Preprocessor input mesh file (mesh file format determined** automatically by filename extension or forced by **-format** sub-option)

- \-sc, --sim-comm

  **simulate messages without file output**

*General options*

- \--cwd \<directory\>

  **working directory (if different from current directory)**

- \-h, --help

  **Print a usage message and exit.**

- \-i, --in \[\<file\>\]

  **Command line completed by a file (default file: standard input)**

- \--int-face \[\<sub-options\>\]

  **Count and display interior faces these faces may be selected with** face-selection sub-options

- \-j, --join \[\<sub-options\>\]

  **Join non-conforming faces; select faces to join with face-selection** sub-options

- \--log \[\<file\>\]

  **Redirect terminal output to a file (default file:** *preprocessor.log)*

- \-p, --perio \<sub-options\>

  **Mesh periodicity defined by argument; joining sub-options for** tolerances and selection of periodic faces with face-selection sub-options

- \--reorient

  **If necessary, correct orientation of cells and faces**

- \--version

  **Print version number**

*Postprocessing options*

- \--case \<name\>

  **Case name (without this option, the default name is:** *preprocess*)

- \--cgns \[\<sub-options\>\]

  **CGNS geometry output**

- \--ensight \[\<sub-options\>\]

  **EnSight Gold geometry output**

- \--med \[\<sub-options\>\]

  **MED 2.3 geometry output**

*Mesh selection sub-options (-m, --mesh)*

- \--format \<keyword\>

  **Selection of mesh file format**

- \--num \<n\>

  **Selection of mesh number in file (if the format allows it)**

- \--grp-cel \<keyword\>

  **Add groups of cells (based on format features/conventions)**\
     \* based on sections: keyword "section"\
     \* based on zones:    keyword "zone"

- \--grp-fac \<keyword\>

  **Add groups of faces (based on format features/conventions)**\
     \* based on sections: keyword "section"\
     \* based on zones:    keyword "zone"

*Available mesh formats (-m, --mesh; --format)*

                                 Extension      Keyword

   CGNS                          .cgns          cgns     \
    pro-STAR/STAR4                .ngeom         ngeom    \
    EnSight (6 or Gold)           .case          ensight  \
    GAMBIT Neutral                .neu           gambit   \
    GMSH                          .msh           gmsh     \
    NUMECA Hex                    .hex           hex      \
    I-deas universal              .unv           unv      \
    MED                           .med           med      \
    Simail (NOPO)                 .des           des      \
    Meta-mesh file                .mesh          meta

*Postprocessing selection sub-options (--cgns, --ensight, --med)*

- \--discard-poly

  **discard polygonal faces (wth more than 4 edges) or polyhedra**

- \--simple

  **force mesh output on a single part (EnSight) or section (CGNS)**

- \--text

  **force text output (EnSight)**

- \--big-endian

  **force binary output to big-endian (EnSight)**

- \--color-to-group

  **transform colors to groups (MED)**

- \--volume

  **activate output of volume mesh (by default if -boundary or -info not** given)

- \--boundary

  **activate output of boundary mesh (by default if -volume or -info not** given)

- \--info

  **activate output of information meshes (by default if -volume or** -boundary not given)

*Periodicity sub-options (-perio, -periodic)*

- \--trans \<tx ty tz\>

  **translation vector**

- \--rota --angle \<alpha\> --dir \<dx dy dz\> \[--invpt \<px py pz\>\]

  **rotation defined by an angle (in degrees) and a direction vector, and** eventually by an invariant point (origin by default)

- \--rota --matrix \<mij\> \[--invpt \<px py pz\>\]

  **rotation defined by the rotation matrix (given line by line), and** eventually by an invariant point (origin by default)

*Non-conformal face joining sub-options (-j, --join, -p, --perio)*

- \--fraction \<real number\>

  **fraction of the length of the smallest edge under which we consider** that vertices may be fused (default value: 0.1)

- \--plane \<real number\>

  **minimal cosine of the normals of 2 coplanar faces (default value: 0.8)**

- \--semi-conf

  **fast joining algorithm (allowed if faces already share vertices)**

*Face selection sub-options (for joining, selection, and periodicity)*

- \--color \<number(s)\>

  **color numbers of faces to select**

- \--group \<name(s)\>

  **group names of faces to select**

- \--invsel

  **invert selection**

## ENVIRONMENT

- CS\_PREPROCESS\_MIN\_EDGE\_LEN

  Length under which an edge is considered degenerate (default: 1.e-15).

- CS\_PREPROCESS\_MEM\_LOG

  Name of memory operations trace file.

- CS\_PREPROCESS\_IGNORE\_IDEAS\_COO\_SYS

  Ignore I-deas coordinate systems.

- CS\_PREPROCESS\_JOIN\_MAX\_SUB\_FACES

  Number of new faces of an initial face above which we consider that conformal joining face reconstruction has gone into an infinite loop (default: 100)

## SEE ALSO

[**cs\_io\_dump**(1)](/cs_io_dump/1.md), [**cs\_partition**(1)](/cs_partition/1.md)