# compute smd/triangle/vertices command

## Syntax

    compute ID group-ID smd/triangle/vertices

-   ID, group-ID are documented in [compute](compute) command
-   smd/triangle/vertices = style name of this compute command

## Examples

``` LAMMPS
compute 1 all smd/triangle/vertices
```

## Description

Define a computation that returns the coordinates of the vertices
corresponding to the triangle-elements of a mesh created by the [fix
smd/wall_surface](fix_smd_wall_surface).

See [this PDF guide](PDF/MACHDYN_LAMMPS_userguide.pdf)\_ to using Smooth
Mach Dynamics in LAMMPS.

## Output info

This compute returns a per-particle vector of vectors, which can be
accessed by any command that uses per-particle values from a compute as
input. See the [Howto output](Howto_output) page for an overview of
LAMMPS output options.

The per-particle vector has nine entries, (x1/y1/z1), (x2/y2/z2), and
(x3/y3/z3) corresponding to the first, second, and third vertex of each
triangle.

It is only meaningful to use this compute for a group of particles which
is created via the [fix smd/wall_surface](fix_smd_wall_surface) command.

The output of this compute can be used with the dump2vtk_tris tool to
generate a VTK representation of the smd/wall_surface mesh for
visualization purposes.

The values will be given in [units](units) of distance.

## Restrictions

This compute is part of the MACHDYN package. It is only enabled if
LAMMPS was built with that package. See the [Build
package](Build_package) page for more info.

## Related commands

[fix smd/move/tri/surf](fix_smd_move_triangulated_surface), [fix
smd/wall_surface](fix_smd_wall_surface)

## Default

none