fix_eos_table.txt
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fix_eos_table.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

			fix eos/table command :h3

			[Syntax:]

			fix ID group-ID eos/table style file N keyword :pre

			ID, group-ID are documented in "fix"_fix.html command
			eos/table = style name of this fix command
			style = {linear} = method of interpolation
			file = filename containing the tabulated equation of state
			N = use N values in {linear} tables
			keyword = name of table keyword corresponding to table file :ul

			[Examples:]

			fix 1 all eos/table linear eos.table 100000 KEYWORD :pre

			[Description:]

			Fix {eos/table} applies a tabulated mesoparticle equation of state to
			relate the particle internal energy (u_i) to the particle internal
			temperature (dpdTheta_i).

			Fix {eos/table} creates interpolation tables of length {N} from
			internal energy values listed in a file as a function of internal
			temperature.

			The interpolation tables are created by fitting cubic splines to the
			file values and interpolating energy values at each of {N} internal
			temperatures, and vice-versa. During a simulation, these tables are
			used to interpolate internal energy or temperature values as needed.
			The interpolation is done with the {linear} style.

			For the {linear} style, the internal temperature is used to find 2
			surrounding table values from which an internal energy is computed by
			linear interpolation, and vice-versa.

			The filename specifies a file containing tabulated internal
			temperature and internal energy values. The keyword specifies a
			section of the file. The format of this file is described below.

			:line

			The format of a tabulated file is as follows (without the
			parenthesized comments):

			# EOS TABLE (one or more comment or blank lines) :pre

			KEYWORD (keyword is first text on line)
			N 500 (N parameter)
			(blank)
			1 1.00 0.000 (index, internal temperature, internal energy)
			2 1.02 0.001
			...
			500 10.0 0.500 :pre

			A section begins with a non-blank line whose 1st character is not a
			"#"; blank lines or lines starting with "#" can be used as comments
			between sections. The first line begins with a keyword which
			identifies the section. The line can contain additional text, but the
			initial text must match the argument specified in the fix command.

			The next line lists the number of table entries. The parameter "N" is
			required and its value is the number of table entries that follow.
			Note that this may be different than the {N} specified in the "fix
			eos/table"_fix_eos_table.html command. Let Ntable = {N} in the fix
			command, and Nfile = "N" in the tabulated file. What LAMMPS does is a
			preliminary interpolation by creating splines using the Nfile
			tabulated values as nodal points. It uses these to interpolate as
			needed to generate energy and temperature values at Ntable different
			points. The resulting tables of length Ntable are then used as
			described above, when computing energy and temperature relationships.
			This means that if you want the interpolation tables of length Ntable
			to match exactly what is in the tabulated file (with effectively no
			preliminary interpolation), you should set Ntable = Nfile.

			Following a blank line, the next N lines list the tabulated values.
			On each line, the 1st value is the index from 1 to N, the 2nd value is
			the internal temperature (in temperature units), the 3rd value is the
			internal energy (in energy units).

			Note that the internal temperature and internal energy values must
			increase from one line to the next.

			Note that one file can contain many sections, each with a tabulated
			potential. LAMMPS reads the file section by section until it finds
			one that matches the specified keyword.

			:line

			[Restrictions:]

			This command is part of the USER-DPD package. It is only enabled if
			LAMMPS was built with that package. See the "Making
			LAMMPS"_Section_start.html#start_3 section for more info.

			This command also requires use of the "atom_style dpd"_atom_style.html
			command.

			The equation of state must be a monotonically increasing function.

			An error will occur if the internal temperature or internal energies
			are not within the table cutoffs.

			[Related commands:]

			"fix shardlow"_fix_shardlow.html, "pair dpd/fdt"_pair_dpd_fdt.html

			[Default:] none

lammps/doc/src/fix_eos_table.txt920641bbffbcmaster

fix_eos_table.txtView Options

lammps/doc/src/fix_eos_table.txt
920641bbffbcmaster

fix_eos_table.txt
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