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<H3>compute_modify command 
</H3>
<P><B>Syntax:</B>
</P>
<PRE>compute_modify compute-ID keyword value ... 
</PRE>
<UL><LI>compute-ID = ID of the compute to modify 

<LI>one or more keyword/value pairs may be listed 

<LI>keyword = <I>extra</I> or <I>dynamic</I> 

<PRE>  <I>extra</I> value = N
    N = # of extra degrees of freedom to subtract
  <I>dynamic</I> value = <I>yes</I> or <I>no</I>
    yes/no = do or do not recompute the number of atoms contributing to the temperature 
</PRE>

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<P><B>Examples:</B>
</P>
<PRE>compute_modify myTemp extra 0
compute_modify newtemp dynamic yes extra 600 
</PRE>
<P><B>Description:</B>
</P>
<P>Modify one or more parameters of a previously defined compute.  Not
all compute styles support all parameters.
</P>
<P>The <I>extra</I> 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 3 which is a correction factor for an
ensemble of velocities with zero total linear momentum.
</P>
<P>The <I>dynamic</I> 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 <A HREF = "fix_pour.html">fix pour</A> or <A HREF = "fix_deposit.html">fix
deposit</A> commands) or expect atoms to be lost
(e.g. due to evaporation), then this option can be used to insure the
temperature is correctly normalized.
</P>
<P><B>Restrictions:</B> none
</P>
<P><B>Related commands:</B>
</P>
<P><A HREF = "compute.html">compute</A>
</P>
<P><B>Default:</B>
</P>
<P>The option defaults are extra = 3 and dynamic = no.
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