# dump cfg/uef command

## Syntax

``` LAMMPS
dump ID group-ID cfg/uef N file mass type xs ys zs args
```

-   ID = user-assigned name for the dump

-   group-ID = ID of the group of atoms to be dumped

-   N = dump every this many timesteps

-   file = name of file to write dump info to

        args = same as args for `dump custom <dump>`__

## Examples

``` LAMMPS
dump 1 all cfg/uef 10 dump.*.cfg mass type xs ys zs
dump 2 all cfg/uef 100 dump.*.cfg mass type xs ys zs id c_stress
```

## Description

This command is used to dump atomic coordinates in the reference frame
of the applied flow field when [fix nvt/uef](fix_nh_uef) or [fix
npt/uef](fix_nh_uef) is used. Only the atomic coordinates and
frame-invariant scalar quantities will be in the flow frame. If
velocities are selected as output, for example, they will not be in the
same reference frame as the atomic positions.

## Restrictions

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

This command can only be used when [fix nvt/uef](fix_nh_uef) or [fix
npt/uef](fix_nh_uef) is active.

## Related commands

[dump](dump), [fix nvt/uef](fix_nh_uef)

## Default

none