# dump atom/adios command

# dump custom/adios command

## Syntax

``` LAMMPS
dump ID group-ID atom/adios N file.bp
dump ID group-ID custom/adios N file.bp args
```

-   ID = user-assigned name for the dump
-   group-ID = ID of the group of atoms to be imaged
-   adios = style of dump command (other styles *atom* or *cfg* or *dcd*
    or *xtc* or *xyz* or *local* or *custom* are discussed on the
    [dump](dump) doc page)
-   N = dump every this many timesteps
-   file.bp = name of file/stream to write to
-   args = same options as in [dump custom](dump) command

## Examples

``` LAMMPS
dump adios1 all atom/adios   100 atoms.bp
dump 4a     all custom/adios 100 dump_adios.bp id v_p x y z
dump 2 subgroup custom/adios 100 dump_adios.bp mass type xs ys zs vx vy vz
```

## Description

Dump a snapshot of atom coordinates every $N$ timesteps in the
[ADIOS](https://github.com/ornladios/ADIOS2)\_-based \"BP\" file format,
or using different I/O solutions in ADIOS, to a stream that can be read
on-line by another program. ADIOS-BP files are binary, portable, and
self-describing.

:::: note
::: title
Note
:::

To be able to use ADIOS, a file `adios2_config.xml` with specific
configuration settings is expected in the current working directory. If
the file is not present, LAMMPS will try to create a minimal default
file. Please refer to the ADIOS documentation for details on how to
adjust this file for optimal performance and desired features.
::::

**Use from write_dump:**

It is possible to use these dump styles with the
[write_dump](write_dump) command. In this case, the sub-intervals must
not be set at all. The write_dump command can be used to create a new
file at each individual dump.

``` LAMMPS
dump 4     all atom/adios 100 dump.bp
write_dump all atom/adios singledump.bp
```

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## Restrictions

The number of atoms per snapshot **can** change with the adios style.
When using the ADIOS tool \'bpls\' to list the content of a .bp file,
bpls will print *\_\_* for the size of the output table indicating that
its size is changing every step.

The *atom/adios* and *custom/adios* dump styles are part of the ADIOS
package. They are only enabled if LAMMPS was built with that package.
See the [Build package](Build_package) page for more info.

------------------------------------------------------------------------

## Related commands

[dump](dump), [dump_modify](dump_modify), [undump](undump)