.. index:: compute smd/tlsph/strain

compute smd/tlsph/strain command
================================

Syntax
""""""

.. parsed-literal::

   compute ID group-ID smd/tlsph/strain

* ID, group-ID are documented in :doc:`compute <compute>` command
* smd/tlsph/strain = style name of this compute command

Examples
""""""""

.. code-block:: LAMMPS

   compute 1 all smd/tlsph/strain

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

Define a computation that calculates the Green-Lagrange strain tensor
for particles interacting via the Total-Lagrangian SPH pair style.

See `this PDF guide <PDF/SMD_LAMMPS_userguide.pdf>`_ to using Smooth
Mach Dynamics in LAMMPS.

Output info
"""""""""""

This compute calculates a per-particle vector of vectors (tensors),
which can be accessed by any command that uses per-particle values
from a compute as input.  See the :doc:`Howto output <Howto_output>` doc
page for an overview of LAMMPS output options.

The per-particle tensor values will be given dimensionless. See
:doc:`units <units>`.

The per-particle vector has 6 entries, corresponding to the xx, yy,
zz, xy, xz, yz components of the symmetric strain tensor.

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

This compute is part of the MACHDYN package.  It is only enabled if
LAMMPS was built with that package.  See the :doc:`Build package <Build_package>` page for more info.

This quantity will be computed only for particles which interact with
the Total-Lagrangian SPH pair style.

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

:doc:`smd/tlsph/strain/rate <compute_smd_tlsph_strain_rate>`,
:doc:`smd/tlsph/stress <compute_smd_tlsph_stress>`

Default
"""""""

none
