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doc/Section_commands.html
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<DIV ALIGN=center><TABLE BORDER=1 >
<TR ALIGN="center"><TD ><A HREF = "compute_centro_atom.html">centro/atom</A></TD><TD ><A HREF = "compute_coord_atom.html">coord/atom</A></TD><TD ><A HREF = "compute_displace_atom.html">displace/atom</A></TD><TD ><A HREF = "compute_group_group.html">group/group</A></TD><TD ><A HREF = "compute_ke_atom.html">ke/atom</A></TD><TD ><A HREF = "compute_pe.html">pe</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "compute_pe_atom.html">pe/atom</A></TD><TD ><A HREF = "compute_pressure.html">pressure</A></TD><TD ><A HREF = "compute_reduce.html">reduce</A></TD><TD ><A HREF = "compute_rotate_dipole.html">rotate/dipole</A></TD><TD ><A HREF = "compute_rotate_gran.html">rotate/gran</A></TD><TD ><A HREF = "compute_stress_atom.html">stress/atom</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "compute_temp.html">temp</A></TD><TD ><A HREF = "compute_temp_asphere.html">temp/asphere</A></TD><TD ><A HREF = "compute_temp_deform.html">temp/deform</A></TD><TD ><A HREF = "compute_temp_dipole.html">temp/dipole</A></TD><TD ><A HREF = "compute_temp_partial.html">temp/partial</A></TD><TD ><A HREF = "compute_temp_ramp.html">temp/ramp</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "compute_temp_region.html">temp/region</A>
<TR ALIGN="center"><TD ><A HREF = "compute_temp.html">temp</A></TD><TD ><A HREF = "compute_temp_asphere.html">temp/asphere</A></TD><TD ><A HREF = "compute_temp_com.html">temp/com</A></TD><TD ><A HREF = "compute_temp_deform.html">temp/deform</A></TD><TD ><A HREF = "compute_temp_dipole.html">temp/dipole</A></TD><TD ><A HREF = "compute_temp_partial.html">temp/partial</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "compute_temp_ramp.html">temp/ramp</A></TD><TD ><A HREF = "compute_temp_region.html">temp/region</A>
</TD></TR></TABLE></DIV>
<P>These are compute styles contributed by users, which can be used if

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doc/Section_commands.txt
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"stress/atom"_compute_stress_atom.html,
"temp"_compute_temp.html,
"temp/asphere"_compute_temp_asphere.html,
"temp/com"_compute_temp_com.html,
"temp/deform"_compute_temp_deform.html,
"temp/dipole"_compute_temp_dipole.html,
"temp/partial"_compute_temp_partial.html,

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doc/compute.html
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<LI><A HREF = "compute_stress_atom.html">stress/atom</A> - stress tensor for each atom
<LI><A HREF = "compute_temp.html">temp</A> - temperature of group of atoms
<LI><A HREF = "compute_temp_asphere.html">temp/asphere</A> - temperature of aspherical particles
<LI><A HREF = "compute_temp_com.html">temp/com</A> - temperature after subtracting c-o-m velocity
<LI><A HREF = "compute_temp_deform.html">temp/deform</A> - temperature excluding box deformation velocity
<LI><A HREF = "compute_temp_dipole.html">temp/dipole</A> - temperature of point dipolar particles
<LI><A HREF = "compute_temp_partial.html">temp/partial</A> - temperature excluding one or more dimensions of velocity

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doc/compute.txt
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"stress/atom"_compute_stress_atom.html - stress tensor for each atom
"temp"_compute_temp.html - temperature of group of atoms
"temp/asphere"_compute_temp_asphere.html - temperature of aspherical particles
"temp/com"_compute_temp_com.html - temperature after subtracting c-o-m velocity
"temp/deform"_compute_temp_deform.html - temperature excluding box deformation velocity
"temp/dipole"_compute_temp_dipole.html - temperature of point dipolar particles
"temp/partial"_compute_temp_partial.html - temperature excluding one or more dimensions of velocity

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<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 temp/com command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>compute ID group-ID temp/com
</PRE>
<UL><LI>ID, group-ID are documented in <A HREF = "compute.html">compute</A> command
<LI>temp/com = style name of this compute command
</UL>
<P><B>Examples:</B>
</P>
<PRE>compute 1 all temp/com
compute myTemp mobile temp/com
</PRE>
<P><B>Description:</B>
</P>
<P>Define a computation that calculates the temperature of a group of
atoms, after subtracting out the center-of-mass velocity of the group.
This is useful if the group is expected to have a non-zero net
velocity for some reason. A compute of this style can be used by any
command that computes a temperature,
e.g. <A HREF = "thermo_modify.html">thermo_modify</A>, <A HREF = "fix_temp_rescale.html">fix
temp/rescale</A>, <A HREF = "fix_npt.html">fix npt</A>, etc.
</P>
<P>The temperature is calculated by the formula KE = dim/2 N k T, where
KE = total kinetic energy of the group of atoms (sum of 1/2 m v^2),
dim = 2 or 3 = dimensionality of the simulation, N = number of atoms
in the group, k = Boltzmann constant, and T = temperature.
</P>
<P>A 6-component kinetic energy tensor is also calculated by this compute
for use in the computation of a pressure tensor. The formula for the
components of the tensor is the same as the above formula, except that
v^2 is replaced by vx * vy for the xy component, etc.
</P>
<P>The number of atoms contributing to the temperature is assumed to be
constant for the duration of the run; use the <I>dynamic</I> option of the
<A HREF = "compute_modify.html">compute_modify</A> command if this is not the case.
</P>
<P>This compute subtracts out degrees-of-freedom due to fixes that
constrain molecular motion, such as <A HREF = "fix_shake.html">fix shake</A> and
<A HREF = "fix_rigid.html">fix rigid</A>. This means the temperature of groups of
atoms that include these constraints will be computed correctly. If
needed, the subtracted degrees-of-freedom can be altered using the
<I>extra</I> option of the <A HREF = "compute_modify.html">compute_modify</A> command.
</P>
<P><B>Output info:</B>
</P>
<P>The scalar value calculated by this compute is "intensive", meaning it
is independent of the number of atoms in the simulation. The vector
values are "extensive", meaning they scale with the number of atoms in
the simulation.
</P>
<P><B>Restrictions:</B> none
</P>
<P><B>Related commands:</B>
</P>
<P><A HREF = "compute_temp.html">compute temp</A>
</P>
<P><B>Default:</B> none
</P>
</HTML>

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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
:link(lws,http://lammps.sandia.gov)
:link(ld,Manual.html)
:link(lc,Section_commands.html#comm)
:line
compute temp/com command :h3
[Syntax:]
compute ID group-ID temp/com :pre
ID, group-ID are documented in "compute"_compute.html command
temp/com = style name of this compute command :ul
[Examples:]
compute 1 all temp/com
compute myTemp mobile temp/com :pre
[Description:]
Define a computation that calculates the temperature of a group of
atoms, after subtracting out the center-of-mass velocity of the group.
This is useful if the group is expected to have a non-zero net
velocity for some reason. A compute of this style can be used by any
command that computes a temperature,
e.g. "thermo_modify"_thermo_modify.html, "fix
temp/rescale"_fix_temp_rescale.html, "fix npt"_fix_npt.html, etc.
The temperature is calculated by the formula KE = dim/2 N k T, where
KE = total kinetic energy of the group of atoms (sum of 1/2 m v^2),
dim = 2 or 3 = dimensionality of the simulation, N = number of atoms
in the group, k = Boltzmann constant, and T = temperature.
A 6-component kinetic energy tensor is also calculated by this compute
for use in the computation of a pressure tensor. The formula for the
components of the tensor is the same as the above formula, except that
v^2 is replaced by vx * vy for the xy component, etc.
The number of atoms contributing to the temperature is assumed to be
constant for the duration of the run; use the {dynamic} option of the
"compute_modify"_compute_modify.html command if this is not the case.
This compute subtracts out degrees-of-freedom due to fixes that
constrain molecular motion, such as "fix shake"_fix_shake.html and
"fix rigid"_fix_rigid.html. This means the temperature of groups of
atoms that include these constraints will be computed correctly. If
needed, the subtracted degrees-of-freedom can be altered using the
{extra} option of the "compute_modify"_compute_modify.html command.
[Output info:]
The scalar value calculated by this compute is "intensive", meaning it
is independent of the number of atoms in the simulation. The vector
values are "extensive", meaning they scale with the number of atoms in
the simulation.
[Restrictions:] none
[Related commands:]
"compute temp"_compute_temp.html
[Default:] none