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@ -956,200 +956,215 @@ particles are point masses.
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<A NAME = "4_15"></A><H4>4.15 Output from LAMMPS (thermo, dumps, computes, fixes, variables)
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</H4>
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<P>Aside from <A HREF = "restart.html">restart files</A>, there are two basic kinds of
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LAMMPS output. The first is <A HREF = "thermo_style.html">thermodynamic output</A>,
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which is a list of quantities printed every few timesteps to the
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screen and logfile. The second is <A HREF = "dump.html">dump files</A>, which
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contain snapshots of atoms and various per-atom values and are written
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at a specified frequency. A simulation prints one set of
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thermodynamic output; it may generate any number of dump files. As
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discussed below, LAMMPS gives you a variety of ways to determine what
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quantities are computed and printed when thermodynamic info or dump
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files are output. There are also three fixes which can do their own
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output of user-chosen quantities: <A HREF = "fix_ave_time.html">fix ave/time</A> for
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time averaging, <A HREF = "fix_ave_spatial.html">fix ave/spatial</A> for spatial
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averaging, and <A HREF = "fix_print.html">fix print</A>. These are also described
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below. Throughout this discussion, note that users can <A HREF = "Section_modify.html">add their own
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computes and fixes to LAMMPS</A> which can then
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generate values that can be output with these commands.
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<P>There are four basic kinds of LAMMPS output:
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</P>
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<H5>Thermodynamic output
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<UL><LI><A HREF = "thermo_style.html">Thermodynamic output</A>, which is a list
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of quantities printed every few timesteps to the screen and logfile.
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<LI><A HREF = "dump.html">Dump files</A>, which contain snapshots of atoms and various
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per-atom values and are written at a specified frequency.
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<LI>Certain fixes can output user-specified quantities to files: <A HREF = "fix_ave_time.html">fix
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ave/time</A> for time averaging, <A HREF = "fix_ave_spatial.html">fix
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ave/spatial</A> for spatial averaging, and <A HREF = "fix_print.html">fix
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print</A> for single-line output of
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<A HREF = "variable.html">variables</A>. Fix print can also output to the
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screen.
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<LI><A HREF = "restart.html">Restart files</A>.
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</UL>
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<P>A simulation prints one set of thermodynamic output and (optionally)
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restart files. It can generate any number of dump files and fix
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output files, depending on what <A HREF = "dump.html">dump</A> and <A HREF = "fix.html">fix</A>
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commands you specify.
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</P>
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<P>As discussed below, LAMMPS gives you a variety of ways to determine
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what quantities are computed and printed when the thermodynamics,
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dump, or fix commands listed above perform output. Throughout this
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discussion, note that users can also <A HREF = "Section_modify.html">add their own computes and fixes
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to LAMMPS</A> which can then generate values that can
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then be output with these commands.
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</P>
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<P>The following sub-sections discuss different LAMMPS command related
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to output and the kind of data they operate on and produce:
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</P>
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<UL><LI><A HREF = "#global">Global/per-atom/local data</A>
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<LI><A HREF = "#scalar">Scalar/vector/array data</A>
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<LI><A HREF = "#thermo">Thermodynamic output</A>
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<LI><A HREF = "#dump">Dump file output</A>
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<LI><A HREF = "#fixoutput">Fixes that write output files</A>
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<LI><A HREF = "#computeoutput">Computes that process output quantities</A>
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<LI><A HREF = "#compute">Computes that generate values to output</A>
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<LI><A HREF = "#fix">Fixes that generate values to output</A>
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<LI><A HREF = "#variable">Variables that generate values to output</A>
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<LI><A HREF = "#table">Summary table of output options and data flow between commands</A>
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</UL>
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<H5><A NAME = "global"></A>Global/per-atom/local data
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</H5>
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<P>Various output-related commands work with three different styles of
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data: global, per-atom, or local. A global datum is one or more
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system-wide values, e.g. the temperature of the system. A per-atom
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datum is one or more values per atom, e.g. the kinetic energy of each
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atom. Local datums are calculated by each processor based on the
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atoms it owns, but there may be zero or more per atom, e.g. a list of
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bond distances.
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</P>
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<H5><A NAME = "scalar"></A>Scalar/vector/array data
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</H5>
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<P>Global, per-atom, and local datums can each come in three kinds: a
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single scalar value, a vector of values, or a 2d array of values. The
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doc page for a "compute" or "fix" or "variable" that generates data
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will specify both the style and kind of data it produces, e.g. a
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per-atom vector.
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</P>
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<P>When a quantity is accessed, as in many of the output commands
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discussed below, it can be referenced via the following bracket
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notation, where ID in this case is the ID of a compute. The leading
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"c_" would be replaced by "f_" for a fix, or "v_" for a variable:
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</P>
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<DIV ALIGN=center><TABLE BORDER=1 >
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<TR><TD >c_ID </TD><TD > entire scalar, vector, or array</TD></TR>
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<TR><TD >c_ID[I] </TD><TD > one element of vector, one column of array</TD></TR>
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<TR><TD >c_ID[I][J] </TD><TD > one element of array
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</TD></TR></TABLE></DIV>
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<P>In other words, using one bracket reduces the dimension of the data
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once (vector -> scalar, array -> vector). Using two brackets reduces
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the dimension twice (array -> scalar). Thus a command that uses
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scalar values as input can typically also process elements of a vector
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or array.
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</P>
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<H5><A NAME = "thermo"></A>Thermodynamic output
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</H5>
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<P>The frequency and format of thermodynamic output is set by the
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<A HREF = "thermo.html">thermo</A>, <A HREF = "thermo_style.html">thermo_style</A>, and
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<A HREF = "thermo_modify.html">thermo_modify</A> commands. The
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<A HREF = "thermo_style.html">thermo_style</A> command also specifies what values are
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calculated and written out. Pre-defined keywords can be specified
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(e.g. press, etotal, etc). Three additional kinds of keywords can also
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be specified (c_ID, f_ID, v_name), where a <A HREF = "compute.html">compute</A> or
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<A HREF = "fix.html">fix</A> or <A HREF = "variable.html">variable</A> provides the value to be
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output. Each of these are described in turn.
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<A HREF = "thermo_style.html">thermo_style</A> command also specifies what values
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are calculated and written out. Pre-defined keywords can be specified
|
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(e.g. press, etotal, etc). Three additional kinds of keywords can
|
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also be specified (c_ID, f_ID, v_name), where a <A HREF = "compute.html">compute</A>
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or <A HREF = "fix.html">fix</A> or <A HREF = "variable.html">variable</A> provides the value to be
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output. In each case, the compute, fix, or variable must generate
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global values for input to the <A HREF = "dump.html">thermo_style custom</A>
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command.
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</P>
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<P>In LAMMPS, a <A HREF = "compute.html">compute</A> comes in two flavors: ones that
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compute global values (a scalar or a vector, e.g. temperature,
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6-element pressure tensor) and ones that compute per-atom values.
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Only global quantities from a compute can be used for thermodynamic
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output. The user-defined ID of the compute is used along with an
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optional subscript as part of the <A HREF = "thermo_style.html">thermo_style</A>
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command. E.g. c_myTemp outputs the single scalar value generated by
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the compute; c_myTemp[2] outputs the 2nd vector value. Note that
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there is a <A HREF = "compute_reduce.html">compute reduce</A> command which can sum
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per-atom quantities into a global scalar or vector.
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</P>
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<P><A HREF = "fix.html">Fixes</A> can generate global scalar or vector values which can
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be output with thermodynamic output, e.g. the energy of an indenter's
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interaction with the simulation atoms. These values are accessed via
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the same format as a compute's values, as f_ID or f_ID[N]. See the
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doc pages for individual fix commands to see which ones generate
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global values that can be output with thermodynamic info. The <A HREF = "fix_ave_time.html">fix
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ave/time</A> command generates time-averaged global
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quantities which can be accessed for thermodynamic output, e.g. a
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time-averaged pressure.
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</P>
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<P><A HREF = "variable.html">Variables</A> can be defined in the input script. All
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styles except the atom-style variable can be used for thermodynamic
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output, since it generates per-atom values. A variable with the name
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"abc" is referenced in a thermo_style command as v_abc.
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</P>
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<P>The formula associated with equal-style variables can contain math
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operations and functions (x+y,x*y,(),sqrt,exp,etc), atom values
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(x[N],fx[N],etc), group functions (mass(),vcm(),etc), references
|
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to thermodynamic quantities (temp,press,vol,etc), references to
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<A HREF = "compute.html">computes</A> that generate global values, references to
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<A HREF = "fix.html">fixes</A> that generate global values, or references to other
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<A HREF = "variable.html">variables</A>. Thus an equal-style variable is the most
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general way to define some quantity to calculate and include with
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thermodynamic output.
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</P>
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<H5>Dump file output
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<H5><A NAME = "dump"></A>Dump file output
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</H5>
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<P>Dump file output is specified by the <A HREF = "dump.html">dump</A> and
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<A HREF = "dump_modify.html">dump_modify</A> commands. There are several
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pre-defined formats (dump atom, dump xtc, etc). There is also a <A HREF = "dump.html">dump
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custom</A> format where the user specifies what values are
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output with each atom. Pre-defined keywords can be specified (tag, x,
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output with each atom. Pre-defined keywords can be specified (id, x,
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fx, etc). Three additional kinds of keywords can also be specified
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(c_ID, f_ID, v_name), where a <A HREF = "compute.html">compute</A> or <A HREF = "fix.html">fix</A>
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or <A HREF = "variable.html">variable</A> provides the value to be output. Each of
|
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these are described in turn.
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or <A HREF = "variable.html">variable</A> provides the values to be output. In each
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case, the compute, fix, or variable must generate per-atom values for
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input to the <A HREF = "dump.html">dump custom</A> command.
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</P>
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<P><A HREF = "compute.html">Computes</A> that generate one or more per-atom values can
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be accessed by the dump custom command. These are computes that have
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the word "atom" in their style name, e.g. ke/atom, stress/atom, etc.
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The values are accessed as c_myKE for a scalar per-atom quantity or as
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c_myStress[2] for a component of a vector per-atom quantity.
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</P>
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<P><A HREF = "fix.html">Fixes</A> can generate per-atom values to output to dump files.
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For example, the <A HREF = "fix_ave_atom.html">fix ave/atom</A> command calculates
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time-averages of per-atom quantities, such as per-atom
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<A HREF = "compute.html">computes</A> and atom-style <A HREF = "variable.html">variables</A>.
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These per-atom fix values are accessed by the <A HREF = "dump.html">dump custom</A>
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command via the same format as a compute's values, as f_myKE or
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f_myStress[2].
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</P>
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<P><A HREF = "variable.html">Variables</A> can be defined in the input script. Only
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atom-style variables can be used for dump custom output, since only
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they produce per-atom values. A variable with the name "abc" is
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referenced in a dump custom command as v_abc.
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</P>
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<P>Just like equal-style variables, the formula associated with
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atom-style variables can contain math operations and functions
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(x+y,x*y,(),sqrt,exp,etc), atom values (x[N],fx[N],etc), group
|
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functions (mass(),vcm(),etc), references to thermodynamic quantities
|
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(temp,press,vol,etc), references to <A HREF = "compute.html">computes</A> that
|
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generate global values, references to <A HREF = "fix.html">fixes</A> that generate
|
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global values, or references to non atom-style variables that generate
|
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global values. In addition, an atom-style variable can reference
|
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vectors of atom values (x[],fx[],etc), <A HREF = "compute.html">computes</A>
|
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that generate per-atom values, <A HREF = "fix.html">fixes</A> that generate per-atom
|
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values, or other atom-style variables. Thus an atom-style variable is
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the most general way to define some quantity to calculate and output
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to a dump file.
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</P>
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<H5>Fix output
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<H5><A NAME = "fixoutput"></A>Fixes that write output files
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</H5>
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<P>Three other fixes are of particular note for output: <A HREF = "fix_ave_time.html">fix
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ave/time</A>, <A HREF = "fix_ave_spatial.html">fix ave/spatial</A>,
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and <A HREF = "fix_print.html">fix print</A>.
|
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<P>Three fixes take various quantities as input and can write output
|
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files: <A HREF = "fix_ave_time.html">fix ave/time</A>, <A HREF = "fix_ave_spatial.html">fix
|
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ave/spatial</A>, and <A HREF = "fix_print.html">fix print</A>.
|
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</P>
|
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<P>The <A HREF = "fix_ave_time.html">fix ave/time</A> command enables time-averaging of
|
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any global quantity, like those output with thermodynamic info. The
|
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user specifies one or more quantities to time average. These can be
|
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global <A HREF = "compute.html">compute</A> values, global <A HREF = "fix.html">fix</A> values, or
|
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<P>The <A HREF = "fix_ave_time.html">fix ave/time</A> command enables direct output to
|
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a file and/or time-averaging of any global quantity. The user
|
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specifies one or more quantities as input. These can be global
|
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<A HREF = "compute.html">compute</A> values, global <A HREF = "fix.html">fix</A> values, or
|
||||
<A HREF = "variable.html">variables</A> of any style except the atom style which
|
||||
produces per-atom values. Since a variable can refer to keywords used
|
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by the <A HREF = "thermo_style.html">thermo_style custom</A> command (like temp or
|
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press), any thermodynamic quantity can be time averaged in this way.
|
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press) and individual per-atom values, a wide variety of quantities
|
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can be time averaged and/or output in this way. The time-averaged
|
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output of this fix can also be used as input to other output commands.
|
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</P>
|
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<P>The <A HREF = "fix_ave_time.html">fix ave/time</A> command offers several options
|
||||
for how it performs time averaging. The results it produces can be
|
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used in two ways. First, they can be written directly to a file, one
|
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line per timestamp. Note that the averaging parameters can be
|
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specified in such a way that averaging is not done at all, in which
|
||||
case this is simply a convenient means of outputting desired
|
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quantities directly to a separate file. Like other fixes that produce
|
||||
global quantities, the results of this fix can also be used as input
|
||||
to any command that accesses global quantities, e.g. by the
|
||||
<A HREF = "thermo_style.html">thermo_style custom</A> command, by a variable, etc.
|
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</P>
|
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<P>The <A HREF = "fix_ave_spatial.html">fix ave/spatial</A> command enables
|
||||
spatial-averaging of per-atom quantities like those output in dump
|
||||
files, within 1d layers of the simulation box. The per-atom
|
||||
quantities can be atom density (mass or number) or atom attributes
|
||||
such as position, velocity, force. They can also be per-atom
|
||||
quantities calculated by a <A HREF = "compute.html">compute</A>, by a
|
||||
<A HREF = "fix.html">fix</A>, or by an atom-style <A HREF = "variable.html">variable</A>.
|
||||
</P>
|
||||
<P>The <A HREF = "fix_ave_spatial.html">fix ave/spatial</A> command offers several
|
||||
options for how it performs time averaging. The per-layer values it
|
||||
produces can be used in two ways. First, they can be written directly
|
||||
to a file. Note that the averaging parameters can be specified in
|
||||
such a way that time averaging is not done, in which case this is a
|
||||
convenient means of simply outputting desired quantities (summed over
|
||||
atoms within a 1d layer) directly to a separate file. Like other
|
||||
fixes that produce global quantities, the results of this fix can also
|
||||
be used as input by any command that accesses global quantities,
|
||||
e.g. by the <A HREF = "thermo_style.html">thermo_style custom</A> command, by a
|
||||
variable, etc. See the doc page for <A HREF = "fix_ave_spatial.html">fix
|
||||
ave/spatial</A> for a description of how these
|
||||
values are indexed.
|
||||
<P>The <A HREF = "fix_ave_spatial.html">fix ave/spatial</A> command enables direct
|
||||
output to a file of spatial-averaged per-atom quantities like those
|
||||
output in dump files, within 1d layers of the simulation box. The
|
||||
per-atom quantities can be atom density (mass or number) or atom
|
||||
attributes such as position, velocity, force. They can also be
|
||||
per-atom quantities calculated by a <A HREF = "compute.html">compute</A>, by a
|
||||
<A HREF = "fix.html">fix</A>, or by an atom-style <A HREF = "variable.html">variable</A>. The
|
||||
spatial-averaged output of this fix can also be used as input to other
|
||||
output commands.
|
||||
</P>
|
||||
<P>The <A HREF = "fix_print.html">fix print</A> command can generate a line of output
|
||||
written to the screen and log file or to a separate file, periodically
|
||||
during a running simulation. The line can contain one or more
|
||||
<A HREF = "variable.html">variable</A> values (for any style variable except the
|
||||
atom style), and as explained above, variables themselves can contain
|
||||
<A HREF = "variable.html">variable</A> values for any style variable except the atom
|
||||
style). As explained above, variables themselves can contain
|
||||
references to global values generated by <A HREF = "thermo_style.html">thermodynamic
|
||||
keywords</A>, <A HREF = "compute.html">computes</A>,
|
||||
<A HREF = "fix.html">fixes</A>, or other <A HREF = "variable.html">variables</A>. Thus the <A HREF = "fix_print.html">fix
|
||||
print</A> command is a means to output any desired
|
||||
calculated quantity separate from normal thermodynamic or dump file
|
||||
output.
|
||||
<A HREF = "fix.html">fixes</A>, or other <A HREF = "variable.html">variables</A>, or to per-atom
|
||||
values for a specific atom. Thus the <A HREF = "fix_print.html">fix print</A>
|
||||
command is a means to output a wide variety of quantities separate
|
||||
from normal thermodynamic or dump file output.
|
||||
</P>
|
||||
<P>This table summarizes the various output options, specifying what
|
||||
their inputs and outputs are. The frequency with which they are
|
||||
invoked and produce output is also listed. Basically, any two
|
||||
commands can be hooked together so long as one produces output that
|
||||
matches the input needs of the other. A "match" means that the
|
||||
frequencies and global vs per-atom attributes are the same.
|
||||
<H5><A NAME = "computeoutput"></A>Computes that process output quantities
|
||||
</H5>
|
||||
<P>The <A HREF = "compute_reduce.html">compute reduce</A> and <A HREF = "compute_reduce.html">compute
|
||||
reduce/region</A> commands take one or more vector
|
||||
quantities as inputs and "reduce" them (sum, min, max, ave) to scalar
|
||||
quantities. These are produced as output values which can be used as
|
||||
input to other output commands.
|
||||
</P>
|
||||
<H5><A NAME = "compute"></A>Computes that generate values to output
|
||||
</H5>
|
||||
<P>Every <A HREF = "compute.html">compute</A> in LAMMPS produces either global or
|
||||
per-atom or local quantities. The quantities can be scalars or
|
||||
vectors or arrays of data. The doc page for each compute command
|
||||
describes what it produces. These values can be output using
|
||||
the other commands described in this section.
|
||||
</P>
|
||||
<H5><A NAME = "fix"></A>Fixes that generate values to output
|
||||
</H5>
|
||||
<P>Some <A HREF = "fix.html">fixes</A> in LAMMPS produces either global or per-atom or
|
||||
local quantities which can be accessed by other commands. The
|
||||
quantities can be scalars or vectors or arrays of data. The doc page
|
||||
for each fix command tells whether it produces any output quantities
|
||||
and describes them. These values can be output using the other
|
||||
commands described in this section.
|
||||
</P>
|
||||
<H5><A NAME = "variable"></A>Variables that generate values to output
|
||||
</H5>
|
||||
<P>Every <A HREF = "variable.html">variables</A> defined in an input script generates
|
||||
either a global scalar value or a per-atom vector (only atom-style
|
||||
variables) when it is accessed. The formulas used to define equal-
|
||||
and atom-style variables can contain references to the thermodynamic
|
||||
keywords and to global and per-atom data generated by computes, fixes,
|
||||
and other variables. The values generated by variables can be output
|
||||
using the other commands described in this section.
|
||||
</P>
|
||||
<H5><A NAME = "table"></A>Summary table of output options and data flow between commands
|
||||
</H5>
|
||||
<P>This table summarizes the various commands that can be used for
|
||||
generating output from LAMMPS. Each command produces output data of
|
||||
some kind and/or writes data to a file. Some of the commands take
|
||||
data from other commands as input. Thus you can link many of these
|
||||
commands together in pipeline form, where data produced by one command
|
||||
is used as input to another command and eventually written to the
|
||||
screen or to a file. Note that to hook two commands together the
|
||||
output and input data types must match, e.g. global/per-atom/local
|
||||
data and scalar/vector/array data.
|
||||
</P>
|
||||
<P>Also note that, as described above, when a command takes a scalar as
|
||||
input, that could be an element of a vector or array. Likewise a
|
||||
vector input could be a column of an array.
|
||||
</P>
|
||||
<DIV ALIGN=center><TABLE BORDER=1 >
|
||||
<TR><TD >Command</TD><TD > Input</TD><TD > Input Freq</TD><TD > Output</TD><TD > Output Freq</TD></TR>
|
||||
<TR><TD >thermo_style custom</TD><TD > thermo keyword, global scalar/vector compute, global scalar/vector fix, equal variable</TD><TD > nthermo</TD><TD > screen, log</TD><TD > nthermo</TD></TR>
|
||||
<TR><TD >dump custom</TD><TD > keyword, per-atom compute, per-atom fix, atom variable</TD><TD > dump freq</TD><TD > file</TD><TD > dump freq</TD></TR>
|
||||
<TR><TD >global fixes</TD><TD > N/A</TD><TD > N/A</TD><TD > global scalar/vector</TD><TD > 1 or nevery</TD></TR>
|
||||
<TR><TD >per-atom fixes</TD><TD > N/A</TD><TD > N/A</TD><TD > per-atom vector/array</TD><TD > 1 or nevery</TD></TR>
|
||||
<TR><TD >fix ave/time</TD><TD > global scalar/vector fix, global scalar/vector compute, equal variable</TD><TD > nevery</TD><TD > global scalar/vector, file</TD><TD > nfreq</TD></TR>
|
||||
<TR><TD >fix ave/spatial</TD><TD > per-atom fix, per-atom compute, atom vector, atom variable, density mass/number</TD><TD > nevery</TD><TD > global vector</TD><TD > nfreq, file</TD></TR>
|
||||
<TR><TD >fix ave/atom</TD><TD > per-atom compute, per-atom fix, atom variable, atom vector</TD><TD > nevery</TD><TD > per-atom vector/array</TD><TD > nfreq</TD></TR>
|
||||
<TR><TD >fix print</TD><TD > any variable</TD><TD > nevery</TD><TD > screen, file</TD><TD > nevery</TD></TR>
|
||||
<TR><TD >global computes</TD><TD > N/A</TD><TD > N/A</TD><TD > global scalar/vector</TD><TD > N/A</TD></TR>
|
||||
<TR><TD >per-atom computes</TD><TD > N/A</TD><TD > N/A</TD><TD > per-atom vector/array</TD><TD > N/A</TD></TR>
|
||||
<TR><TD >compute sum</TD><TD > per-atom compute, per-atom fix, atom variable</TD><TD > N/A</TD><TD > global scalar/vector</TD><TD > N/A</TD></TR>
|
||||
<TR><TD >variable equal</TD><TD > thermo keywords, atom value vx[123], global scalar/vector compute, global scalar/vector fix, non-atom variable</TD><TD > N/A</TD><TD > global scalar</TD><TD > N/A</TD></TR>
|
||||
<TR><TD >variable atom</TD><TD > thermo keywords, atom value vx[123], atom vector vx[], global scalar/vector compute, per-atom compute, global fix, per-atom fix, any variable</TD><TD > N/A</TD><TD > per-atom vector</TD><TD > N/A</TD></TR>
|
||||
<TR><TD >print</TD><TD > any variable</TD><TD > N/A</TD><TD > screen, log</TD><TD > between runs</TD></TR>
|
||||
<TR><TD >run every</TD><TD > any variable</TD><TD > nevery</TD><TD > screen, log</TD><TD > nevery
|
||||
<TR><TD >Command</TD><TD > Input</TD><TD > Output</TD><TD ></TD></TR>
|
||||
<TR><TD >thermo_style custom</TD><TD > global scalars</TD><TD > screen, log file</TD><TD ></TD></TR>
|
||||
<TR><TD >dump custom</TD><TD > per-atom vectors</TD><TD > dump file</TD><TD ></TD></TR>
|
||||
<TR><TD >fix print</TD><TD > global scalar from variable</TD><TD > screen, file</TD><TD ></TD></TR>
|
||||
<TR><TD >print</TD><TD > global scalar from variable</TD><TD > screen</TD><TD ></TD></TR>
|
||||
<TR><TD >computes</TD><TD > N/A</TD><TD > global/per-atom/local scalar/vector/array</TD><TD ></TD></TR>
|
||||
<TR><TD >fixes</TD><TD > N/A</TD><TD > global/per-atom/local scalar/vector/array</TD><TD ></TD></TR>
|
||||
<TR><TD >variables</TD><TD > global scalars, per-atom vectors</TD><TD > global scalar, per-atom vector</TD><TD ></TD></TR>
|
||||
<TR><TD >compute reduce</TD><TD > global/per-atom/local vectors</TD><TD > global scalar/vector</TD><TD ></TD></TR>
|
||||
<TR><TD >fix ave/time</TD><TD > global scalars</TD><TD > global scalar/vector, file</TD><TD ></TD></TR>
|
||||
<TR><TD >fix ave/spatial</TD><TD > per-atom vectors/arrays</TD><TD > global array, file</TD><TD ></TD></TR>
|
||||
<TR><TD >fix ave/atom</TD><TD > per-atom vectors</TD><TD > per-atom vector/array</TD><TD ></TD></TR>
|
||||
<TR><TD >
|
||||
</TD></TR></TABLE></DIV>
|
||||
|
||||
<HR>
|
||||
|
|
|
|||
|
|
@ -949,199 +949,212 @@ particles are point masses.
|
|||
|
||||
4.15 Output from LAMMPS (thermo, dumps, computes, fixes, variables) :link(4_15),h4
|
||||
|
||||
Aside from "restart files"_restart.html, there are two basic kinds of
|
||||
LAMMPS output. The first is "thermodynamic output"_thermo_style.html,
|
||||
which is a list of quantities printed every few timesteps to the
|
||||
screen and logfile. The second is "dump files"_dump.html, which
|
||||
contain snapshots of atoms and various per-atom values and are written
|
||||
at a specified frequency. A simulation prints one set of
|
||||
thermodynamic output; it may generate any number of dump files. As
|
||||
discussed below, LAMMPS gives you a variety of ways to determine what
|
||||
quantities are computed and printed when thermodynamic info or dump
|
||||
files are output. There are also three fixes which can do their own
|
||||
output of user-chosen quantities: "fix ave/time"_fix_ave_time.html for
|
||||
time averaging, "fix ave/spatial"_fix_ave_spatial.html for spatial
|
||||
averaging, and "fix print"_fix_print.html. These are also described
|
||||
below. Throughout this discussion, note that users can "add their own
|
||||
computes and fixes to LAMMPS"_Section_modify.html which can then
|
||||
generate values that can be output with these commands.
|
||||
There are four basic kinds of LAMMPS output:
|
||||
|
||||
Thermodynamic output :h5
|
||||
"Thermodynamic output"_thermo_style.html, which is a list
|
||||
of quantities printed every few timesteps to the screen and logfile. :ulb,l
|
||||
|
||||
"Dump files"_dump.html, which contain snapshots of atoms and various
|
||||
per-atom values and are written at a specified frequency. :l
|
||||
|
||||
Certain fixes can output user-specified quantities to files: "fix
|
||||
ave/time"_fix_ave_time.html for time averaging, "fix
|
||||
ave/spatial"_fix_ave_spatial.html for spatial averaging, and "fix
|
||||
print"_fix_print.html for single-line output of
|
||||
"variables"_variable.html. Fix print can also output to the
|
||||
screen. :l
|
||||
|
||||
"Restart files"_restart.html. :l,ule
|
||||
|
||||
A simulation prints one set of thermodynamic output and (optionally)
|
||||
restart files. It can generate any number of dump files and fix
|
||||
output files, depending on what "dump"_dump.html and "fix"_fix.html
|
||||
commands you specify.
|
||||
|
||||
As discussed below, LAMMPS gives you a variety of ways to determine
|
||||
what quantities are computed and printed when the thermodynamics,
|
||||
dump, or fix commands listed above perform output. Throughout this
|
||||
discussion, note that users can also "add their own computes and fixes
|
||||
to LAMMPS"_Section_modify.html which can then generate values that can
|
||||
then be output with these commands.
|
||||
|
||||
The following sub-sections discuss different LAMMPS command related
|
||||
to output and the kind of data they operate on and produce:
|
||||
|
||||
"Global/per-atom/local data"_#global
|
||||
"Scalar/vector/array data"_#scalar
|
||||
"Thermodynamic output"_#thermo
|
||||
"Dump file output"_#dump
|
||||
"Fixes that write output files"_#fixoutput
|
||||
"Computes that process output quantities"_#computeoutput
|
||||
"Computes that generate values to output"_#compute
|
||||
"Fixes that generate values to output"_#fix
|
||||
"Variables that generate values to output"_#variable
|
||||
"Summary table of output options and data flow between commands"_#table :ul
|
||||
|
||||
Global/per-atom/local data :h5,link(global)
|
||||
|
||||
Various output-related commands work with three different styles of
|
||||
data: global, per-atom, or local. A global datum is one or more
|
||||
system-wide values, e.g. the temperature of the system. A per-atom
|
||||
datum is one or more values per atom, e.g. the kinetic energy of each
|
||||
atom. Local datums are calculated by each processor based on the
|
||||
atoms it owns, but there may be zero or more per atom, e.g. a list of
|
||||
bond distances.
|
||||
|
||||
Scalar/vector/array data :h5,link(scalar)
|
||||
|
||||
Global, per-atom, and local datums can each come in three kinds: a
|
||||
single scalar value, a vector of values, or a 2d array of values. The
|
||||
doc page for a "compute" or "fix" or "variable" that generates data
|
||||
will specify both the style and kind of data it produces, e.g. a
|
||||
per-atom vector.
|
||||
|
||||
When a quantity is accessed, as in many of the output commands
|
||||
discussed below, it can be referenced via the following bracket
|
||||
notation, where ID in this case is the ID of a compute. The leading
|
||||
"c_" would be replaced by "f_" for a fix, or "v_" for a variable:
|
||||
|
||||
c_ID | entire scalar, vector, or array
|
||||
c_ID\[I\] | one element of vector, one column of array
|
||||
c_ID\[I\]\[J\] | one element of array :tb(s=|)
|
||||
|
||||
In other words, using one bracket reduces the dimension of the data
|
||||
once (vector -> scalar, array -> vector). Using two brackets reduces
|
||||
the dimension twice (array -> scalar). Thus a command that uses
|
||||
scalar values as input can typically also process elements of a vector
|
||||
or array.
|
||||
|
||||
Thermodynamic output :h5,link(thermo)
|
||||
|
||||
The frequency and format of thermodynamic output is set by the
|
||||
"thermo"_thermo.html, "thermo_style"_thermo_style.html, and
|
||||
"thermo_modify"_thermo_modify.html commands. The
|
||||
"thermo_style"_thermo_style.html command also specifies what values are
|
||||
calculated and written out. Pre-defined keywords can be specified
|
||||
(e.g. press, etotal, etc). Three additional kinds of keywords can also
|
||||
be specified (c_ID, f_ID, v_name), where a "compute"_compute.html or
|
||||
"fix"_fix.html or "variable"_variable.html provides the value to be
|
||||
output. Each of these are described in turn.
|
||||
"thermo_style"_thermo_style.html command also specifies what values
|
||||
are calculated and written out. Pre-defined keywords can be specified
|
||||
(e.g. press, etotal, etc). Three additional kinds of keywords can
|
||||
also be specified (c_ID, f_ID, v_name), where a "compute"_compute.html
|
||||
or "fix"_fix.html or "variable"_variable.html provides the value to be
|
||||
output. In each case, the compute, fix, or variable must generate
|
||||
global values for input to the "thermo_style custom"_dump.html
|
||||
command.
|
||||
|
||||
In LAMMPS, a "compute"_compute.html comes in two flavors: ones that
|
||||
compute global values (a scalar or a vector, e.g. temperature,
|
||||
6-element pressure tensor) and ones that compute per-atom values.
|
||||
Only global quantities from a compute can be used for thermodynamic
|
||||
output. The user-defined ID of the compute is used along with an
|
||||
optional subscript as part of the "thermo_style"_thermo_style.html
|
||||
command. E.g. c_myTemp outputs the single scalar value generated by
|
||||
the compute; c_myTemp\[2\] outputs the 2nd vector value. Note that
|
||||
there is a "compute reduce"_compute_reduce.html command which can sum
|
||||
per-atom quantities into a global scalar or vector.
|
||||
|
||||
"Fixes"_fix.html can generate global scalar or vector values which can
|
||||
be output with thermodynamic output, e.g. the energy of an indenter's
|
||||
interaction with the simulation atoms. These values are accessed via
|
||||
the same format as a compute's values, as f_ID or f_ID\[N\]. See the
|
||||
doc pages for individual fix commands to see which ones generate
|
||||
global values that can be output with thermodynamic info. The "fix
|
||||
ave/time"_fix_ave_time.html command generates time-averaged global
|
||||
quantities which can be accessed for thermodynamic output, e.g. a
|
||||
time-averaged pressure.
|
||||
|
||||
"Variables"_variable.html can be defined in the input script. All
|
||||
styles except the atom-style variable can be used for thermodynamic
|
||||
output, since it generates per-atom values. A variable with the name
|
||||
"abc" is referenced in a thermo_style command as v_abc.
|
||||
|
||||
The formula associated with equal-style variables can contain math
|
||||
operations and functions (x+y,x*y,(),sqrt,exp,etc), atom values
|
||||
(x\[N\],fx\[N\],etc), group functions (mass(),vcm(),etc), references
|
||||
to thermodynamic quantities (temp,press,vol,etc), references to
|
||||
"computes"_compute.html that generate global values, references to
|
||||
"fixes"_fix.html that generate global values, or references to other
|
||||
"variables"_variable.html. Thus an equal-style variable is the most
|
||||
general way to define some quantity to calculate and include with
|
||||
thermodynamic output.
|
||||
|
||||
Dump file output :h5
|
||||
Dump file output :h5,link(dump)
|
||||
|
||||
Dump file output is specified by the "dump"_dump.html and
|
||||
"dump_modify"_dump_modify.html commands. There are several
|
||||
pre-defined formats (dump atom, dump xtc, etc). There is also a "dump
|
||||
custom"_dump.html format where the user specifies what values are
|
||||
output with each atom. Pre-defined keywords can be specified (tag, x,
|
||||
output with each atom. Pre-defined keywords can be specified (id, x,
|
||||
fx, etc). Three additional kinds of keywords can also be specified
|
||||
(c_ID, f_ID, v_name), where a "compute"_compute.html or "fix"_fix.html
|
||||
or "variable"_variable.html provides the value to be output. Each of
|
||||
these are described in turn.
|
||||
or "variable"_variable.html provides the values to be output. In each
|
||||
case, the compute, fix, or variable must generate per-atom values for
|
||||
input to the "dump custom"_dump.html command.
|
||||
|
||||
"Computes"_compute.html that generate one or more per-atom values can
|
||||
be accessed by the dump custom command. These are computes that have
|
||||
the word "atom" in their style name, e.g. ke/atom, stress/atom, etc.
|
||||
The values are accessed as c_myKE for a scalar per-atom quantity or as
|
||||
c_myStress\[2\] for a component of a vector per-atom quantity.
|
||||
Fixes that write output files :h5,link(fixoutput)
|
||||
|
||||
"Fixes"_fix.html can generate per-atom values to output to dump files.
|
||||
For example, the "fix ave/atom"_fix_ave_atom.html command calculates
|
||||
time-averages of per-atom quantities, such as per-atom
|
||||
"computes"_compute.html and atom-style "variables"_variable.html.
|
||||
These per-atom fix values are accessed by the "dump custom"_dump.html
|
||||
command via the same format as a compute's values, as f_myKE or
|
||||
f_myStress\[2\].
|
||||
Three fixes take various quantities as input and can write output
|
||||
files: "fix ave/time"_fix_ave_time.html, "fix
|
||||
ave/spatial"_fix_ave_spatial.html, and "fix print"_fix_print.html.
|
||||
|
||||
"Variables"_variable.html can be defined in the input script. Only
|
||||
atom-style variables can be used for dump custom output, since only
|
||||
they produce per-atom values. A variable with the name "abc" is
|
||||
referenced in a dump custom command as v_abc.
|
||||
|
||||
Just like equal-style variables, the formula associated with
|
||||
atom-style variables can contain math operations and functions
|
||||
(x+y,x*y,(),sqrt,exp,etc), atom values (x\[N\],fx\[N\],etc), group
|
||||
functions (mass(),vcm(),etc), references to thermodynamic quantities
|
||||
(temp,press,vol,etc), references to "computes"_compute.html that
|
||||
generate global values, references to "fixes"_fix.html that generate
|
||||
global values, or references to non atom-style variables that generate
|
||||
global values. In addition, an atom-style variable can reference
|
||||
vectors of atom values (x\[\],fx\[\],etc), "computes"_compute.html
|
||||
that generate per-atom values, "fixes"_fix.html that generate per-atom
|
||||
values, or other atom-style variables. Thus an atom-style variable is
|
||||
the most general way to define some quantity to calculate and output
|
||||
to a dump file.
|
||||
|
||||
Fix output :h5
|
||||
|
||||
Three other fixes are of particular note for output: "fix
|
||||
ave/time"_fix_ave_time.html, "fix ave/spatial"_fix_ave_spatial.html,
|
||||
and "fix print"_fix_print.html.
|
||||
|
||||
The "fix ave/time"_fix_ave_time.html command enables time-averaging of
|
||||
any global quantity, like those output with thermodynamic info. The
|
||||
user specifies one or more quantities to time average. These can be
|
||||
global "compute"_compute.html values, global "fix"_fix.html values, or
|
||||
The "fix ave/time"_fix_ave_time.html command enables direct output to
|
||||
a file and/or time-averaging of any global quantity. The user
|
||||
specifies one or more quantities as input. These can be global
|
||||
"compute"_compute.html values, global "fix"_fix.html values, or
|
||||
"variables"_variable.html of any style except the atom style which
|
||||
produces per-atom values. Since a variable can refer to keywords used
|
||||
by the "thermo_style custom"_thermo_style.html command (like temp or
|
||||
press), any thermodynamic quantity can be time averaged in this way.
|
||||
press) and individual per-atom values, a wide variety of quantities
|
||||
can be time averaged and/or output in this way. The time-averaged
|
||||
output of this fix can also be used as input to other output commands.
|
||||
|
||||
The "fix ave/time"_fix_ave_time.html command offers several options
|
||||
for how it performs time averaging. The results it produces can be
|
||||
used in two ways. First, they can be written directly to a file, one
|
||||
line per timestamp. Note that the averaging parameters can be
|
||||
specified in such a way that averaging is not done at all, in which
|
||||
case this is simply a convenient means of outputting desired
|
||||
quantities directly to a separate file. Like other fixes that produce
|
||||
global quantities, the results of this fix can also be used as input
|
||||
to any command that accesses global quantities, e.g. by the
|
||||
"thermo_style custom"_thermo_style.html command, by a variable, etc.
|
||||
|
||||
The "fix ave/spatial"_fix_ave_spatial.html command enables
|
||||
spatial-averaging of per-atom quantities like those output in dump
|
||||
files, within 1d layers of the simulation box. The per-atom
|
||||
quantities can be atom density (mass or number) or atom attributes
|
||||
such as position, velocity, force. They can also be per-atom
|
||||
quantities calculated by a "compute"_compute.html, by a
|
||||
"fix"_fix.html, or by an atom-style "variable"_variable.html.
|
||||
|
||||
The "fix ave/spatial"_fix_ave_spatial.html command offers several
|
||||
options for how it performs time averaging. The per-layer values it
|
||||
produces can be used in two ways. First, they can be written directly
|
||||
to a file. Note that the averaging parameters can be specified in
|
||||
such a way that time averaging is not done, in which case this is a
|
||||
convenient means of simply outputting desired quantities (summed over
|
||||
atoms within a 1d layer) directly to a separate file. Like other
|
||||
fixes that produce global quantities, the results of this fix can also
|
||||
be used as input by any command that accesses global quantities,
|
||||
e.g. by the "thermo_style custom"_thermo_style.html command, by a
|
||||
variable, etc. See the doc page for "fix
|
||||
ave/spatial"_fix_ave_spatial.html for a description of how these
|
||||
values are indexed.
|
||||
The "fix ave/spatial"_fix_ave_spatial.html command enables direct
|
||||
output to a file of spatial-averaged per-atom quantities like those
|
||||
output in dump files, within 1d layers of the simulation box. The
|
||||
per-atom quantities can be atom density (mass or number) or atom
|
||||
attributes such as position, velocity, force. They can also be
|
||||
per-atom quantities calculated by a "compute"_compute.html, by a
|
||||
"fix"_fix.html, or by an atom-style "variable"_variable.html. The
|
||||
spatial-averaged output of this fix can also be used as input to other
|
||||
output commands.
|
||||
|
||||
The "fix print"_fix_print.html command can generate a line of output
|
||||
written to the screen and log file or to a separate file, periodically
|
||||
during a running simulation. The line can contain one or more
|
||||
"variable"_variable.html values (for any style variable except the
|
||||
atom style), and as explained above, variables themselves can contain
|
||||
"variable"_variable.html values for any style variable except the atom
|
||||
style). As explained above, variables themselves can contain
|
||||
references to global values generated by "thermodynamic
|
||||
keywords"_thermo_style.html, "computes"_compute.html,
|
||||
"fixes"_fix.html, or other "variables"_variable.html. Thus the "fix
|
||||
print"_fix_print.html command is a means to output any desired
|
||||
calculated quantity separate from normal thermodynamic or dump file
|
||||
output.
|
||||
"fixes"_fix.html, or other "variables"_variable.html, or to per-atom
|
||||
values for a specific atom. Thus the "fix print"_fix_print.html
|
||||
command is a means to output a wide variety of quantities separate
|
||||
from normal thermodynamic or dump file output.
|
||||
|
||||
This table summarizes the various output options, specifying what
|
||||
their inputs and outputs are. The frequency with which they are
|
||||
invoked and produce output is also listed. Basically, any two
|
||||
commands can be hooked together so long as one produces output that
|
||||
matches the input needs of the other. A "match" means that the
|
||||
frequencies and global vs per-atom attributes are the same.
|
||||
Computes that process output quantities :h5,link(computeoutput)
|
||||
|
||||
Command: Input: Input Freq: Output: Output Freq
|
||||
thermo_style custom: thermo keyword, global scalar/vector compute, global scalar/vector fix, equal variable: nthermo: screen, log: nthermo
|
||||
dump custom: keyword, per-atom compute, per-atom fix, atom variable: dump freq: file: dump freq
|
||||
global fixes: N/A: N/A: global scalar/vector: 1 or nevery
|
||||
per-atom fixes: N/A: N/A: per-atom vector/array: 1 or nevery
|
||||
fix ave/time: global scalar/vector fix, global scalar/vector compute, equal variable: nevery: global scalar/vector, file: nfreq
|
||||
fix ave/spatial: per-atom fix, per-atom compute, atom vector, atom variable, density mass/number: nevery: global vector: nfreq, file
|
||||
fix ave/atom: per-atom compute, per-atom fix, atom variable, atom vector: nevery: per-atom vector/array: nfreq
|
||||
fix print: any variable: nevery: screen, file: nevery
|
||||
global computes: N/A: N/A: global scalar/vector: N/A
|
||||
per-atom computes: N/A: N/A: per-atom vector/array: N/A
|
||||
compute sum: per-atom compute, per-atom fix, atom variable: N/A: global scalar/vector: N/A
|
||||
variable equal: thermo keywords, atom value vx\[123\], global scalar/vector compute, global scalar/vector fix, non-atom variable: N/A: global scalar: N/A
|
||||
variable atom: thermo keywords, atom value vx\[123\], atom vector vx\[\], global scalar/vector compute, per-atom compute, global fix, per-atom fix, any variable: N/A: per-atom vector: N/A
|
||||
print: any variable: N/A: screen, log: between runs
|
||||
run every: any variable: nevery: screen, log: nevery :tb(s=:)
|
||||
The "compute reduce"_compute_reduce.html and "compute
|
||||
reduce/region"_compute_reduce.html commands take one or more vector
|
||||
quantities as inputs and "reduce" them (sum, min, max, ave) to scalar
|
||||
quantities. These are produced as output values which can be used as
|
||||
input to other output commands.
|
||||
|
||||
Computes that generate values to output :h5,link(compute)
|
||||
|
||||
Every "compute"_compute.html in LAMMPS produces either global or
|
||||
per-atom or local quantities. The quantities can be scalars or
|
||||
vectors or arrays of data. The doc page for each compute command
|
||||
describes what it produces. These values can be output using
|
||||
the other commands described in this section.
|
||||
|
||||
Fixes that generate values to output :h5,link(fix)
|
||||
|
||||
Some "fixes"_fix.html in LAMMPS produces either global or per-atom or
|
||||
local quantities which can be accessed by other commands. The
|
||||
quantities can be scalars or vectors or arrays of data. The doc page
|
||||
for each fix command tells whether it produces any output quantities
|
||||
and describes them. These values can be output using the other
|
||||
commands described in this section.
|
||||
|
||||
Variables that generate values to output :h5,link(variable)
|
||||
|
||||
Every "variables"_variable.html defined in an input script generates
|
||||
either a global scalar value or a per-atom vector (only atom-style
|
||||
variables) when it is accessed. The formulas used to define equal-
|
||||
and atom-style variables can contain references to the thermodynamic
|
||||
keywords and to global and per-atom data generated by computes, fixes,
|
||||
and other variables. The values generated by variables can be output
|
||||
using the other commands described in this section.
|
||||
|
||||
Summary table of output options and data flow between commands :h5,link(table)
|
||||
|
||||
This table summarizes the various commands that can be used for
|
||||
generating output from LAMMPS. Each command produces output data of
|
||||
some kind and/or writes data to a file. Some of the commands take
|
||||
data from other commands as input. Thus you can link many of these
|
||||
commands together in pipeline form, where data produced by one command
|
||||
is used as input to another command and eventually written to the
|
||||
screen or to a file. Note that to hook two commands together the
|
||||
output and input data types must match, e.g. global/per-atom/local
|
||||
data and scalar/vector/array data.
|
||||
|
||||
Also note that, as described above, when a command takes a scalar as
|
||||
input, that could be an element of a vector or array. Likewise a
|
||||
vector input could be a column of an array.
|
||||
|
||||
Command: Input: Output:
|
||||
thermo_style custom: global scalars: screen, log file:
|
||||
dump custom: per-atom vectors: dump file:
|
||||
fix print: global scalar from variable: screen, file:
|
||||
print: global scalar from variable: screen:
|
||||
computes: N/A: global/per-atom/local scalar/vector/array:
|
||||
fixes: N/A: global/per-atom/local scalar/vector/array:
|
||||
variables: global scalars, per-atom vectors: global scalar, per-atom vector:
|
||||
compute reduce: global/per-atom/local vectors: global scalar/vector:
|
||||
fix ave/time: global scalars: global scalar/vector, file:
|
||||
fix ave/spatial: per-atom vectors/arrays: global array, file:
|
||||
fix ave/atom: per-atom vectors: per-atom vector/array:
|
||||
:tb(s=:)
|
||||
|
||||
:line
|
||||
|
||||
|
|
|
|||
|
|
@ -32,7 +32,12 @@ compute 3 all ke/atom
|
|||
Quantities calculated by a compute are instantaneous values, meaning
|
||||
they are calculated from information about atoms on the current
|
||||
timestep or iteration, though a compute may internally store some
|
||||
information about a previous state of the system.
|
||||
information about a previous state of the system. Defining a compute
|
||||
does not perform a computation. Instead computes are invoked by other
|
||||
LAMMPS commands as needed, e.g. to calculate a temperature needed for
|
||||
a thermostat fix or to generate thermodynamic or dump file output.
|
||||
See this <A HREF = "Section_howto.html#4_15">howto section</A> for a summary of
|
||||
various LAMMPS output options, many of which involve computes.
|
||||
</P>
|
||||
<P>The ID of a compute can only contain alphanumeric characters and
|
||||
underscores.
|
||||
|
|
@ -109,9 +114,6 @@ variable</A>.
|
|||
reduce</A> command, or histogrammed by the <A HREF = "fix_ave_histo.html">fix
|
||||
ave/histo</A> command.
|
||||
</UL>
|
||||
<P>See this <A HREF = "Section_howto.html#4_15">howto section</A> for a summary of
|
||||
various LAMMPS output options, many of which involve computes.
|
||||
</P>
|
||||
<P>The results of computes that calculate global quantities can be either
|
||||
"intensive" or "extensive" values. Intensive means the value is
|
||||
independent of the number of atoms in the simulation,
|
||||
|
|
|
|||
|
|
@ -29,7 +29,12 @@ Define a computation that will be performed on a group of atoms.
|
|||
Quantities calculated by a compute are instantaneous values, meaning
|
||||
they are calculated from information about atoms on the current
|
||||
timestep or iteration, though a compute may internally store some
|
||||
information about a previous state of the system.
|
||||
information about a previous state of the system. Defining a compute
|
||||
does not perform a computation. Instead computes are invoked by other
|
||||
LAMMPS commands as needed, e.g. to calculate a temperature needed for
|
||||
a thermostat fix or to generate thermodynamic or dump file output.
|
||||
See this "howto section"_Section_howto.html#4_15 for a summary of
|
||||
various LAMMPS output options, many of which involve computes.
|
||||
|
||||
The ID of a compute can only contain alphanumeric characters and
|
||||
underscores.
|
||||
|
|
@ -104,9 +109,6 @@ Local values can be reduced by the "compute
|
|||
reduce"_compute_reduce.html command, or histogrammed by the "fix
|
||||
ave/histo"_fix_ave_histo.html command. :l,ule
|
||||
|
||||
See this "howto section"_Section_howto.html#4_15 for a summary of
|
||||
various LAMMPS output options, many of which involve computes.
|
||||
|
||||
The results of computes that calculate global quantities can be either
|
||||
"intensive" or "extensive" values. Intensive means the value is
|
||||
independent of the number of atoms in the simulation,
|
||||
|
|
|
|||
Loading…
Reference in New Issue