68 lines
1.8 KiB
ReStructuredText
68 lines
1.8 KiB
ReStructuredText
.. index:: compute smd/tlsph/shape
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compute smd/tlsph/shape command
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===============================
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Syntax
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""""""
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.. parsed-literal::
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compute ID group-ID smd/tlsph/shape
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* ID, group-ID are documented in :doc:`compute <compute>` command
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* smd/tlsph/shape = style name of this compute command
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Examples
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""""""""
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.. code-block:: LAMMPS
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compute 1 all smd/tlsph/shape
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Description
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"""""""""""
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Define a computation that outputs the current shape of the volume
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associated with a particle as a rotated ellipsoid. It is only
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meaningful for particles which interact according to the
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Total-Lagrangian SPH pair style.
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See `this PDF guide <PDF/SMD_LAMMPS_userguide.pdf>`_ to use Smooth
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Mach Dynamics in LAMMPS.
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Output info
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"""""""""""
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This compute calculates a per-particle vector of vectors, which can be
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accessed by any command that uses per-particle values from a compute
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as input. See the :doc:`Howto output <Howto_output>` doc page for an
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overview of LAMMPS output options.
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The per-particle vector has 7 entries. The first three entries
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correspond to the lengths of the ellipsoid's axes and have units of
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length. These axis values are computed as the contact radius times the
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xx, yy, or zz components of the Green-Lagrange strain tensor
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associated with the particle. The next 4 values are quaternions
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(order: q, x, y, z) which describe the spatial rotation of the
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particle relative to its initial state.
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Restrictions
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""""""""""""
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This compute is part of the USER-SMD package. It is only enabled if
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LAMMPS was built with that package. See the :doc:`Build package <Build_package>` doc page for more info.
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This quantity will be computed only for particles which interact with
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the Total-Lagrangian SPH pair style.
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Related commands
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""""""""""""""""
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:doc:`smd/contact/radius <compute_smd_contact_radius>`
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Default
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"""""""
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none
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