lammps/doc/compute_modify.txt

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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_modify command :h3
[Syntax:]
compute_modify compute-ID keyword value ... :pre
compute-ID = ID of the compute to modify :ulb,l
one or more keyword/value pairs may be listed :l
keyword = {extra} or {dynamic} :l
{extra} value = N
N = # of extra degrees of freedom to subtract
{dynamic} value = {yes} or {no}
yes/no = do or do not recompute the number of atoms contributing to the temperature
{thermo} value = {yes} or {no}
yes/no = do or do not add contributions from fixes to the potential energy :pre
:ule
[Examples:]
compute_modify myTemp extra 0
compute_modify newtemp dynamic yes extra 600 :pre
[Description:]
Modify one or more parameters of a previously defined compute. Not
all compute styles support all parameters.
The {extra} keyword refers to how many degrees-of-freedom are
subtracted (typically from 3N) as a normalizing factor in a
temperature computation. Only computes that compute a temperature use
this option. The default is 2 or 3 for "2d or 3d
systems"_dimension.html which is a correction factor for an ensemble
of velocities with zero total linear momentum. You can use a negative
number for the {extra} parameter if you need to add
degrees-of-freedom. See the "compute
temp/asphere"_compute_temp_asphere.html command for an example.
The {dynamic} keyword determines whether the number of atoms N in the
compute group is re-computed each time a temperature is computed.
Only compute styles that compute a temperature use this option. By
default, N is assumed to be constant. If you are adding atoms to the
system (see the "fix pour"_fix_pour.html or "fix
deposit"_fix_deposit.html commands) or expect atoms to be lost
(e.g. due to evaporation), then this option should be used to insure
the temperature is correctly normalized.
The {thermo} keyword determines whether the potential energy
contribution calculated by some "fixes"_fix.html is added to the
potential energy calculated by the compute. Currently, only the
compute of style {pe} uses this option. See the doc pages for
"individual fixes"_fix.html for details.
[Restrictions:] none
[Related commands:]
"compute"_compute.html
[Default:]
The option defaults are extra = 2 or 3 for 2d or 3d systems and
dynamic = no. Thermo is {yes} if the compute of style {pe} was
defined with no extra keywords; otherwise it is {no}.