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@ -32,11 +32,18 @@
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<I>xyz</I> args = Nx Ny Nz
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Nx,Ny,Nz = number of velocity bins in x,y,z dimensions
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</PRE>
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<LI>zero or more keyword/value pairs may be appended
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<LI>keyword = <I>out</I>
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<PRE> <I>out</I> value = <I>tensor</I> or <I>bin</I>
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</PRE>
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</UL>
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<P><B>Examples:</B>
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</P>
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<PRE>compute myTemp flow temp/profile 1 1 1 x 10
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compute myTemp flow temp/profile 1 1 1 x 10 out bin
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compute myTemp flow temp/profile 0 1 1 xyz 20 20 20
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</PRE>
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<P><B>Description:</B>
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@ -77,12 +84,17 @@ T, where KE = total kinetic energy of the group of atoms (sum of 1/2 m
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v^2), dim = 2 or 3 = dimensionality of the simulation, N = number of
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atoms in the group, k = Boltzmann constant, and T = temperature.
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</P>
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<P>A kinetic energy tensor, stored as a 6-element vector, is also
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calculated by this compute for use in the computation of a pressure
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tensor. The formula for the components of the tensor is the same as
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the above formula, except that v^2 is replaced by vx*vy for the xy
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component, etc. The 6 components of the vector are ordered xx, yy,
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zz, xy, xz, yz.
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<P>If the <I>out</I> keyword is used with a <I>tensor</I> value, which is the
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default, a kinetic energy tensor, stored as a 6-element vector, is
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also calculated by this compute for use in the computation of a
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pressure tensor. The formula for the components of the tensor is the
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same as the above formula, except that v^2 is replaced by vx*vy for
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the xy component, etc. The 6 components of the vector are ordered xx,
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yy, zz, xy, xz, yz.
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</P>
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<P>If the <I>out</I> keyword is used with a <I>bin</I> value, the count of atoms
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and computed temperature for each bin are stored for output, as an
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array of values, as described below.
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</P>
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<P>The number of atoms contributing to the temperature is assumed to be
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constant for the duration of the run; use the <I>dynamic</I> option of the
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@ -106,6 +118,12 @@ atoms that include these constraints will be computed correctly. If
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needed, the subtracted degrees-of-freedom can be altered using the
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<I>extra</I> option of the <A HREF = "compute_modify.html">compute_modify</A> command.
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</P>
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<P>IMPORTANT NOTE: When using the <I>out</I> keyword with a value of <I>bin</I>,
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the calculated temperature for each bin does not include the
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degrees-of-freedom adjustment described in the preceeding paragraph,
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for fixes that constrain molecular motion. It does include the
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adjustment due to the <I>extra</I> option, which is applied to each bin.
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</P>
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<P>See <A HREF = "Section_howto.html#howto_16">this howto section</A> of the manual for
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a discussion of different ways to compute temperature and perform
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thermostatting. Using this compute in conjunction with a
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@ -114,18 +132,32 @@ profile-unbiased thermostat (PUT), as described in <A HREF = "#Evans">(Evans)</A
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</P>
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<P><B>Output info:</B>
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</P>
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<P>This compute calculates a global scalar (the temperature) and a global
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vector of length 6 (KE tensor), which can be accessed by indices 1-6.
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These values can be used by any command that uses global scalar or
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vector values from a compute as input. See <A HREF = "Section_howto.html#howto_15">this
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<P>This compute calculates a global scalar (the temperature). Depending
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on the setting of the <I>out</I> keyword, it also calculates a global
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vector or array. For <I>out</I> = <I>tensor</I>, it calculates a vector of
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length 6 (KE tensor), which can be accessed by indices 1-6. For <I>out</I>
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= <I>bin</I> it calculates a global array which has 2 columns and N rows,
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where N is the number of bins. The first column contains the number
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of atoms in that bin. The second contains the temperature of that
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bin, calculated as described above. The ordering of rows in the array
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is as follows. Bins in x vary fastest, then y, then z. Thus for a
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10x10x10 3d array of bins, there will be 1000 rows. The bin with
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indices ix,iy,iz = 2,3,4 would map to row M = (iz-1)*10*10 + (iy-1)*10
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+ ix = 322, where the rows are numbered from 1 to 1000 and the bin
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indices are numbered from 1 to 10 in each dimension.
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</P>
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<P>These values can be used by any command that uses global scalar or
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vector or array values from a compute as input. See <A HREF = "Section_howto.html#howto_15">this
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section</A> for an overview of LAMMPS output
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options.
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</P>
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<P>The scalar value calculated by this compute is "intensive". The
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vector values are "extensive".
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vector values are "extensive". The array values are "intensive".
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</P>
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<P>The scalar value will be in temperature <A HREF = "units.html">units</A>. The
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vector values will be in energy <A HREF = "units.html">units</A>.
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vector values will be in energy <A HREF = "units.html">units</A>. The first column
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of array values are counts; the values in the second column will be in
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temperature <A HREF = "units.html">units</A>.
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</P>
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<P><B>Restrictions:</B>
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</P>
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@ -144,7 +176,7 @@ pressure</A>
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</P>
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<P><B>Default:</B>
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</P>
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<P>The option default is units = lattice.
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<P>The option default is out = tensor.
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</P>
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<HR>
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@ -24,11 +24,16 @@ binstyle = {x} or {y} or {z} or {xy} or {yz} or {xz} or {xyz} :l
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{xz} args = Nx Nz
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{xyz} args = Nx Ny Nz
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Nx,Ny,Nz = number of velocity bins in x,y,z dimensions :pre
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zero or more keyword/value pairs may be appended :l
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keyword = {out} :l
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{out} value = {tensor} or {bin} :pre
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:ule
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[Examples:]
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compute myTemp flow temp/profile 1 1 1 x 10
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compute myTemp flow temp/profile 1 1 1 x 10 out bin
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compute myTemp flow temp/profile 0 1 1 xyz 20 20 20 :pre
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[Description:]
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@ -69,12 +74,17 @@ T, where KE = total kinetic energy of the group of atoms (sum of 1/2 m
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v^2), dim = 2 or 3 = dimensionality of the simulation, N = number of
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atoms in the group, k = Boltzmann constant, and T = temperature.
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A kinetic energy tensor, stored as a 6-element vector, is also
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calculated by this compute for use in the computation of a pressure
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tensor. The formula for the components of the tensor is the same as
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the above formula, except that v^2 is replaced by vx*vy for the xy
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component, etc. The 6 components of the vector are ordered xx, yy,
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zz, xy, xz, yz.
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If the {out} keyword is used with a {tensor} value, which is the
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default, a kinetic energy tensor, stored as a 6-element vector, is
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also calculated by this compute for use in the computation of a
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pressure tensor. The formula for the components of the tensor is the
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same as the above formula, except that v^2 is replaced by vx*vy for
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the xy component, etc. The 6 components of the vector are ordered xx,
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yy, zz, xy, xz, yz.
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If the {out} keyword is used with a {bin} value, the count of atoms
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and computed temperature for each bin are stored for output, as an
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array of values, as described below.
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The number of atoms contributing to the temperature is assumed to be
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constant for the duration of the run; use the {dynamic} option of the
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@ -98,6 +108,12 @@ atoms that include these constraints will be computed correctly. If
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needed, the subtracted degrees-of-freedom can be altered using the
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{extra} option of the "compute_modify"_compute_modify.html command.
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IMPORTANT NOTE: When using the {out} keyword with a value of {bin},
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the calculated temperature for each bin does not include the
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degrees-of-freedom adjustment described in the preceeding paragraph,
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for fixes that constrain molecular motion. It does include the
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adjustment due to the {extra} option, which is applied to each bin.
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See "this howto section"_Section_howto.html#howto_16 of the manual for
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a discussion of different ways to compute temperature and perform
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thermostatting. Using this compute in conjunction with a
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@ -106,18 +122,32 @@ profile-unbiased thermostat (PUT), as described in "(Evans)"_#Evans.
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[Output info:]
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This compute calculates a global scalar (the temperature) and a global
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vector of length 6 (KE tensor), which can be accessed by indices 1-6.
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This compute calculates a global scalar (the temperature). Depending
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on the setting of the {out} keyword, it also calculates a global
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vector or array. For {out} = {tensor}, it calculates a vector of
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length 6 (KE tensor), which can be accessed by indices 1-6. For {out}
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= {bin} it calculates a global array which has 2 columns and N rows,
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where N is the number of bins. The first column contains the number
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of atoms in that bin. The second contains the temperature of that
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bin, calculated as described above. The ordering of rows in the array
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is as follows. Bins in x vary fastest, then y, then z. Thus for a
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10x10x10 3d array of bins, there will be 1000 rows. The bin with
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indices ix,iy,iz = 2,3,4 would map to row M = (iz-1)*10*10 + (iy-1)*10
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+ ix = 322, where the rows are numbered from 1 to 1000 and the bin
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indices are numbered from 1 to 10 in each dimension.
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These values can be used by any command that uses global scalar or
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vector values from a compute as input. See "this
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vector or array values from a compute as input. See "this
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section"_Section_howto.html#howto_15 for an overview of LAMMPS output
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options.
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The scalar value calculated by this compute is "intensive". The
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vector values are "extensive".
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vector values are "extensive". The array values are "intensive".
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The scalar value will be in temperature "units"_units.html. The
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vector values will be in energy "units"_units.html.
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vector values will be in energy "units"_units.html. The first column
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of array values are counts; the values in the second column will be in
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temperature "units"_units.html.
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[Restrictions:]
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@ -136,7 +166,7 @@ pressure"_compute_pressure.html
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[Default:]
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The option default is units = lattice.
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The option default is out = tensor.
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:line
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