forked from lijiext/lammps
87 lines
2.8 KiB
Plaintext
87 lines
2.8 KiB
Plaintext
.. index:: compute angle/local
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compute angle/local 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 angle/local input1 input2 ...
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* ID, group-ID are documented in :doc:`compute <compute>` command
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* angle/local = style name of this compute command
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* one or more keywords may be appended
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* keyword = *theta* or *eng*
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.. parsed-literal::
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*theta* = tabulate angles
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*eng* = tabulate angle energies
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Examples
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""""""""
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.. parsed-literal::
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compute 1 all angle/local theta
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compute 1 all angle/local eng theta
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Description
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"""""""""""
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Define a computation that calculates properties of individual angle
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interactions. The number of datums generated, aggregated across all
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processors, equals the number of angles in the system, modified by the
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group parameter as explained below.
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The local data stored by this command is generated by looping over all
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the atoms owned on a processor and their angles. An angle will only
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be included if all 3 atoms in the angle are in the specified compute
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group. Any angles that have been broken (see the
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:doc:`angle_style <angle_style>` command) by setting their angle type to
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0 are not included. Angles that have been turned off (see the :doc:`fix shake <fix_shake>` or :doc:`delete_bonds <delete_bonds>` commands) by
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setting their angle type negative are written into the file, but their
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energy will be 0.0.
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Note that as atoms migrate from processor to processor, there will be
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no consistent ordering of the entries within the local vector or array
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from one timestep to the next. The only consistency that is
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guaranteed is that the ordering on a particular timestep will be the
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same for local vectors or arrays generated by other compute commands.
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For example, angle output from the :doc:`compute property/local <compute_property_local>` command can be combined
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with data from this command and output by the :doc:`dump local <dump>`
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command in a consistent way.
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**Output info:**
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This compute calculates a local vector or local array depending on the
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number of keywords. The length of the vector or number of rows in the
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array is the number of angles. If a single keyword is specified, a
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local vector is produced. If two or more keywords are specified, a
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local array is produced where the number of columns = the number of
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keywords. The vector or array can be accessed by any command that
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uses local values from a compute as input. See :ref:`this section <howto_15>` for an overview of LAMMPS output
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options.
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The output for *theta* will be in degrees. The output for *eng* will
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be in energy :doc:`units <units>`.
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Restrictions
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""""""""""""
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none
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Related commands
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""""""""""""""""
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:doc:`dump local <dump>`, :doc:`compute property/local <compute_property_local>`
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**Default:** none
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.. _lws: http://lammps.sandia.gov
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.. _ld: Manual.html
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.. _lc: Section_commands.html#comm
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