.. index:: dimension

dimension command
=================

Syntax
""""""

.. parsed-literal::

   dimension N

* N = 2 or 3

Examples
""""""""

.. parsed-literal::

   dimension 2

Description
"""""""""""

Set the dimensionality of the simulation.  By default LIGGGHTS(R)-PUBLIC runs 3d
simulations.  To run a 2d simulation, this command should be used
prior to setting up a simulation box via the
:doc:`create_box <create_box>` or :doc:`read_data <read_data>` commands.
Restart files also store this setting.

See the discussion in :doc:`Section_howto <Section_howto>` for
additional instructions on how to run 2d simulations.

.. warning::

   Some models in LIGGGHTS(R)-PUBLIC treat particles as finite-size
   spheres or ellipsoids, as opposed to point particles.  In 2d, the
   particles will still be spheres or ellipsoids, not circular disks or
   ellipses, meaning their moment of inertia will be the same as in 3d.

Restrictions
""""""""""""


This command must be used before the simulation box is defined by a
:doc:`read_data <read_data>` or :doc:`create_box <create_box>` command.

Related commands
""""""""""""""""

:doc:`fix enforce2d <fix_enforce2d>`

Default
"""""""

.. parsed-literal::

   dimension 3


.. _liws: http://www.cfdem.com
.. _ld: Manual.html
.. _lc: Section_commands.html#comm