forked from lijiext/lammps
55 lines
1.7 KiB
HTML
55 lines
1.7 KiB
HTML
<HTML>
|
|
<CENTER><A HREF = "http://lammps.sandia.gov">LAMMPS WWW Site</A> - <A HREF = "Manual.html">LAMMPS Documentation</A> - <A HREF = "Section_commands.html#comm">LAMMPS Commands</A>
|
|
</CENTER>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<HR>
|
|
|
|
<H3>compute sum/atom command
|
|
</H3>
|
|
<P><B>Syntax:</B>
|
|
</P>
|
|
<PRE>compute ID group-ID sum/atom compute-ID1 compute-ID2 ...
|
|
</PRE>
|
|
<UL><LI>ID, group-ID are documented in <A HREF = "compute.html">compute</A> command
|
|
<LI>sum/atom = style name of this compute command
|
|
<LI>compute-ID1, 2, ... = IDs of computes that calculate per-atom quantities
|
|
</UL>
|
|
<P><B>Examples:</B>
|
|
</P>
|
|
<PRE>compute 1 all sum/atom atomKE atomEpair atomEbond
|
|
</PRE>
|
|
<P><B>Description:</B>
|
|
</P>
|
|
<P>Define a computation that sums the results of two or more other
|
|
computes for each atom in a group. This is useful for summing atom
|
|
properties such as pairwise energy, bond energy, kinetic energy, etc.
|
|
The resulting values can be accessed by any command that uses per-atom
|
|
computes, e.g. the <A HREF = "dump.html">dump custom</A> command or <A HREF = "fix_ave_spatial.html">fix
|
|
ave/spatial</A> command or <A HREF = "fix_ave_atom.html">fix
|
|
ave/atom</A> command.
|
|
</P>
|
|
<P>The value of the sum will be 0.0 for atoms not in the specified
|
|
compute group.
|
|
</P>
|
|
<P>The result of this compute depends on the results generated by the
|
|
other computes that it invokes. E.g. if the other computes each
|
|
generate a scalar value per atom, so will this compute. If the other
|
|
computes each generate a vector of values per atom, so will this
|
|
compute. In the latter case, all the other computes must generate
|
|
per-atom vectors of the same size.
|
|
</P>
|
|
<P><B>Restrictions:</B> none
|
|
</P>
|
|
<P><B>Related commands:</B>
|
|
</P>
|
|
<P><A HREF = "compute_sum.html">compute sum</A>
|
|
</P>
|
|
<P><B>Default:</B> none
|
|
</P>
|
|
</HTML>
|