git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@5257 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
sjplimp
2010-11-18 17:28:36 +00:00
parent 61dcd4156e
commit 37b51e682f
16 changed files with 296 additions and 126 deletions

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@ -114,11 +114,23 @@ underscores, or punctuation characters.
line are arguments.
</P>
<P>(6) If you want text with spaces to be treated as a single argument,
it can be enclosed in double quotes. The quotes are removed when the
single argument is stored in its final form. See the <A HREF = "dump_modify.html">dump modify
format</A> or <A HREF = "if.html">if</A> commands for examples. A "#"
or "$" character that is between double quotes will not be treated as
a comment indicator in (2) or substituted for as a variable in (3).
it can be enclosed in either double or single quotes. E.g.
</P>
<PRE>print "Volume = $v"
print 'Volume = $v'
</PRE>
<P>The quotes are removed when the single argument is stored internally.
See the <A HREF = "dump_modify.html">dump modify format</A> or <A HREF = "if.html">if</A> commands
for examples. A "#" or "$" character that is between quotes will not
be treated as a comment indicator in (2) or substituted for as a
variable in (3).
</P>
<P>IMPORTANT NOTE: If the argument is itself a command that requires a
quoted argument (e.g. using a <A HREF = "print.html">print</A> command as part of an
<A HREF = "if.html">if</A> or <A HREF = "run.html">run every</A> command), then the double and
single quotes can be nested in the usual manner. See the doc pages
for those commands for examples. Only one of level of nesting is
allowed, but that should be sufficient for most use cases.
</P>
<HR>

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@ -111,11 +111,23 @@ underscores, or punctuation characters.
line are arguments.
(6) If you want text with spaces to be treated as a single argument,
it can be enclosed in double quotes. The quotes are removed when the
single argument is stored in its final form. See the "dump modify
format"_dump_modify.html or "if"_if.html commands for examples. A "#"
or "$" character that is between double quotes will not be treated as
a comment indicator in (2) or substituted for as a variable in (3).
it can be enclosed in either double or single quotes. E.g.
print "Volume = $v"
print 'Volume = $v' :pre
The quotes are removed when the single argument is stored internally.
See the "dump modify format"_dump_modify.html or "if"_if.html commands
for examples. A "#" or "$" character that is between quotes will not
be treated as a comment indicator in (2) or substituted for as a
variable in (3).
IMPORTANT NOTE: If the argument is itself a command that requires a
quoted argument (e.g. using a "print"_print.html command as part of an
"if"_if.html or "run every"_run.html command), then the double and
single quotes can be nested in the usual manner. See the doc pages
for those commands for examples. Only one of level of nesting is
allowed, but that should be sufficient for most use cases.
:line

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@ -19,7 +19,8 @@
</P>
<PRE>angle_style class2
angle_coeff * 75.0
angle_coeff 1 bb 10.5872 1.0119 1.5228
angle_coeff 1 bb 10.5872 1.0119 1.5228
angle_coeff * ba 3.6551 24.895 1.0119 1.5228
</PRE>
<P><B>Description:</B>
</P>

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@ -16,7 +16,8 @@ angle_style class2 :pre
angle_style class2
angle_coeff * 75.0
angle_coeff 1 bb 10.5872 1.0119 1.5228 :pre
angle_coeff 1 bb 10.5872 1.0119 1.5228
angle_coeff * ba 3.6551 24.895 1.0119 1.5228 :pre
[Description:]

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@ -18,7 +18,12 @@
<P><B>Examples:</B>
</P>
<PRE>dihedral_style class2
dihedral_coeff 1 100 75 100 70 80 60
dihedral_coeff 1 100 75 100 70 80 60
dihedral_coeff * mbt 3.5945 0.1704 -0.5490 1.5228
dihedral_coeff * ebt 0.3417 0.3264 -0.9036 0.1368 0.0 -0.8080 1.0119 1.1010
dihedral_coeff 2 at 0.0 -0.1850 -0.7963 -2.0220 0.0 -0.3991 110.2453 105.1270
dihedral_coeff * aat -13.5271 110.2453 105.1270
dihedral_coeff * bb13 0.0 1.0119 1.1010
</PRE>
<P><B>Description:</B>
</P>

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@ -15,7 +15,12 @@ dihedral_style class2 :pre
[Examples:]
dihedral_style class2
dihedral_coeff 1 100 75 100 70 80 60 :pre
dihedral_coeff 1 100 75 100 70 80 60
dihedral_coeff * mbt 3.5945 0.1704 -0.5490 1.5228
dihedral_coeff * ebt 0.3417 0.3264 -0.9036 0.1368 0.0 -0.8080 1.0119 1.1010
dihedral_coeff 2 at 0.0 -0.1850 -0.7963 -2.0220 0.0 -0.3991 110.2453 105.1270
dihedral_coeff * aat -13.5271 110.2453 105.1270
dihedral_coeff * bb13 0.0 1.0119 1.1010 :pre
[Description:]

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@ -13,64 +13,81 @@
</H3>
<P><B>Syntax:</B>
</P>
<PRE>if value1 operator value2 then t1 t2 ... else e1 e2 ...
<PRE>if boolean then t1 t2 ... elif boolean f1 f2 ... elif boolean f1 f2 ... else e1 e2 ...
</PRE>
<UL><LI>value1 = 1st value
<LI>operator = "<" or "<=" or ">" or ">=" or "==" or "!="
<LI>value2 = 2nd value
<UL><LI>boolean = a Boolean expression evaluated as TRUE or FALSE (see below)
<LI>then = required word
<LI>t1,t2,...,tN = one or more LAMMPS commands to execute if condition is met, each enclosed in quotes
<LI>elif = optional word, can appear multiple times
<LI>f1,f2,...,fN = one or more LAMMPS commands to execute if elif condition is met, each enclosed in quotes (optional arguments)
<LI>else = optional argument
<LI>e1,e2,...,eN = one or more LAMMPS commands to execute if condition is not met, each enclosed in quotes (optional arguments)
<LI>e1,e2,...,eN = one or more LAMMPS commands to execute if no condition is met, each enclosed in quotes (optional arguments)
</UL>
<P><B>Examples:</B>
</P>
<PRE>if ${steps} > 1000 then exit
if $x <= $y then "print X is smaller = $x" else "print Y is smaller = $y"
if ${eng} > 0.0 then "timestep 0.005"
if ${eng} > ${eng_previous} then "jump file1" else "jump file2"
<PRE>if "${steps} > 1000" then exit
if "$x <= $y" then "print X is smaller = $x" else "print Y is smaller = $y"
if "(${eng} > 0.0) || ($n < 1000)" then &
"timestep 0.005" &
elif $n<10000 &
"timestep 0.01" &
else &
"timestep 0.02" &
"print 'Max step reached'"
if "${eng} > ${eng_previous}" then "jump file1" else "jump file2"
</PRE>
<P><B>Description:</B>
</P>
<P>This command provides an in-then-else capability within an input
script. Two values are numerically compared to each other and the
result is TRUE or FALSE. Note that as in the examples above, either
of the two values can be variables, as defined by the
<A HREF = "variable.html">variable</A> command, so that when the if command is
executed, the variable(s) will be evaluated, which could calculate a
user-defined formula that reflects the current state of the
simulation.
script. A Boolean expression is evaluted and the result is TRUE or
FALSE. Note that as in the examples above, the expression can contain
variables, as defined by the <A HREF = "variable.html">variable</A> command, which
will be evaluated as part of the expression. Thus a user-defined
formula that reflects the current state of the simulation can be used
to issue one or more new commands.
</P>
<P>If the result of the if test is TRUE, then one or more commands (t1,
t2, ..., tN) are executed. If the result of the if test is FALSE and
no optional "else" argument is included, then the if command does
nothing. If the result of the if test is FALSE and the optional
"else" argument is included, then one or more commands (e1,
e2, ..., eN) are executed.
<P>If the result of the Boolean expression is TRUE, then one or more
commands (t1, t2, ..., tN) are executed. If it is FALSE, then Boolean
expressions associated with successive elif keywords are evaluated
until one is found to be true, in which case its commands (f1, f2,
..., fN) are executed. If no Boolean expression is TRUE, then the
commands associated witht the else keyword, namely (e1, e2, ..., eN),
are executed. The elif and else keywords and their associated
commands are optional. If they aren't specified and the initial
Boolean expression is FALSE, then no commands are executed.
</P>
<P>Each then or else command (t1, e1, etc) can be any valid LAMMPS input
script command. Each command should be enclosed in quotes, so it will
be treated as a single argument, as in the examples above.
<P>The allowed syntax for each Boolean expression is described below.
</P>
<P>Each command (t1, f1, e1, etc) can be any valid LAMMPS input script
command. If the command is more than one word, it must enclosed in
quotes, so it will be treated as a single argument, as in the examples
above.
</P>
<P>IMPORTANT NOTE: If a command itself requires a quoted argument (e.g. a
<A HREF = "print.html">print</A> command), then double and single quotes can be used
and nested in the usual manner, as in the examples above and below.
See <A HREF = "Section_commands.html#3_2">this section</A> of the manual for more
details on using quotes in arguments. Only one of level of nesting is
allowed, but that should be sufficient for most use cases.
</P>
<P>Note that by using the line continuation character "&", the if command
can be spread across many lines, though it is still a single
command:
can be spread across many lines, though it is still a single command:
</P>
<PRE>if $a < $b then &
"print Minimum value = $a" &
<PRE>if "$a < $b" then &
"print 'Minimum value = $a'" &
"run 1000" &
else &
"print Minimum value = $b" &
'print "Minimum value = $b"' &
"minimize 0.001 0.001 1000 10000"
</PRE>
<P>Note that if any executed comand is a bogus LAMMPS command, such as
"exit" in the first example above, then executing the command will
cause LAMMPS to halt.
<P>Note that if one of the commands to execute is an invalid LAMMPS
command, such as "exit" in the first example above, then executing the
command will cause LAMMPS to halt.
</P>
<P>Note that by jumping to a label in the same input script, the if
command can be used to break out of a loop. See the <A HREF = "variable.html">variable
delete</A> for info on how to delete the associated loop
variable, so that it can be re-used later in the input script.
delete</A> command for info on how to delete the associated
loop variable, so that it can be re-used later in the input script.
</P>
<P>Here is an example of a double loop which uses the if and
<A HREF = "jump.html">jump</A> commands to break out of the inner loop when a
@ -82,7 +99,7 @@ variable a loop 5
variable b loop 5
print "A,B = $a,$b"
run 10000
if $b > 2 then "jump in.script break"
if '$b > 2' then "print 'Jumping to another script'" "jump in.script break"
next b
jump in.script loopb
label break
@ -91,6 +108,52 @@ variable b delete
<PRE>next a
jump in.script loopa
</PRE>
<HR>
<P>The Boolean expressions for the if and elif keywords have a C-like
syntax. Note that each expression is a single argument within the if
command. Thus if you want to include spaces in the expression for
clarity, you must enclose the entire expression in quotes.
</P>
<P>An expression is built out of numbers
</P>
<PRE>0.2, 100, 1.0e20, -15.4, etc
</PRE>
<P>and Boolean operators:
</P>
<PRE>A == B
A != B
A < B
A <= B
A > B
A >= B
A && B
A || B
</PRE>
<P>Each A and B is a number or a variable reference like $a or ${abc},
or another Boolean expression.
</P>
<P>If a variable is used it must produce a number when evaluated and
substituted for in the expression.
</P>
<P>Expressions are evaluated left to right and have the usual C-style
precedence: the 4 relational operators "<", "<=", ">", and ">=" have
the highest precedence; those 4 relational operators before the
remaining two relational operators "==" and "!="; those two relational
operators before the logical AND operator "&&"; and the AND operator
"&&" before the logical OR operator "||". Parenthesis can be used to
group one or more portions of an expression and/or enforce a different
order of evaluation than what would occur with the default precedence.
</P>
<P>The 6 relational operators return either a 1.0 or 0.0 depending on
whether the relationship between x and y is true or false. The
logical AND operator will return 1.0 of both its arguments are
non-zero, else return a 0.0. The logical OR operator will return 1.0
of either of its arguments is non-zero, else return a 0.0.
</P>
<P>The overall Boolean expression produces a TRUE result if the result is
non-zero. If the result is zero, the expression result is FALSE.
</P>
<P><B>Restrictions:</B> none
</P>
<P><B>Related commands:</B>

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@ -10,64 +10,81 @@ if command :h3
[Syntax:]
if value1 operator value2 then t1 t2 ... else e1 e2 ... :pre
if boolean then t1 t2 ... elif boolean f1 f2 ... elif boolean f1 f2 ... else e1 e2 ... :pre
value1 = 1st value
operator = "<" or "<=" or ">" or ">=" or "==" or "!="
value2 = 2nd value
boolean = a Boolean expression evaluated as TRUE or FALSE (see below)
then = required word
t1,t2,...,tN = one or more LAMMPS commands to execute if condition is met, each enclosed in quotes
elif = optional word, can appear multiple times
f1,f2,...,fN = one or more LAMMPS commands to execute if elif condition is met, each enclosed in quotes (optional arguments)
else = optional argument
e1,e2,...,eN = one or more LAMMPS commands to execute if condition is not met, each enclosed in quotes (optional arguments) :ul
e1,e2,...,eN = one or more LAMMPS commands to execute if no condition is met, each enclosed in quotes (optional arguments) :ul
[Examples:]
if $\{steps\} > 1000 then exit
if $x <= $y then "print X is smaller = $x" else "print Y is smaller = $y"
if $\{eng\} > 0.0 then "timestep 0.005"
if $\{eng\} > $\{eng_previous\} then "jump file1" else "jump file2" :pre
if "$\{steps\} > 1000" then exit
if "$x <= $y" then "print X is smaller = $x" else "print Y is smaller = $y"
if "($\{eng\} > 0.0) || ($n < 1000)" then &
"timestep 0.005" &
elif $n<10000 &
"timestep 0.01" &
else &
"timestep 0.02" &
"print 'Max step reached'"
if "$\{eng\} > $\{eng_previous\}" then "jump file1" else "jump file2" :pre
[Description:]
This command provides an in-then-else capability within an input
script. Two values are numerically compared to each other and the
result is TRUE or FALSE. Note that as in the examples above, either
of the two values can be variables, as defined by the
"variable"_variable.html command, so that when the if command is
executed, the variable(s) will be evaluated, which could calculate a
user-defined formula that reflects the current state of the
simulation.
script. A Boolean expression is evaluted and the result is TRUE or
FALSE. Note that as in the examples above, the expression can contain
variables, as defined by the "variable"_variable.html command, which
will be evaluated as part of the expression. Thus a user-defined
formula that reflects the current state of the simulation can be used
to issue one or more new commands.
If the result of the if test is TRUE, then one or more commands (t1,
t2, ..., tN) are executed. If the result of the if test is FALSE and
no optional "else" argument is included, then the if command does
nothing. If the result of the if test is FALSE and the optional
"else" argument is included, then one or more commands (e1,
e2, ..., eN) are executed.
If the result of the Boolean expression is TRUE, then one or more
commands (t1, t2, ..., tN) are executed. If it is FALSE, then Boolean
expressions associated with successive elif keywords are evaluated
until one is found to be true, in which case its commands (f1, f2,
..., fN) are executed. If no Boolean expression is TRUE, then the
commands associated witht the else keyword, namely (e1, e2, ..., eN),
are executed. The elif and else keywords and their associated
commands are optional. If they aren't specified and the initial
Boolean expression is FALSE, then no commands are executed.
Each then or else command (t1, e1, etc) can be any valid LAMMPS input
script command. Each command should be enclosed in quotes, so it will
be treated as a single argument, as in the examples above.
The syntax for Boolean expressions is described below.
Each command (t1, f1, e1, etc) can be any valid LAMMPS input script
command. If the command is more than one word, it must enclosed in
quotes, so it will be treated as a single argument, as in the examples
above.
IMPORTANT NOTE: If a command itself requires a quoted argument (e.g. a
"print"_print.html command), then double and single quotes can be used
and nested in the usual manner, as in the examples above and below.
See "this section"_Section_commands.html#3_2 of the manual for more
details on using quotes in arguments. Only one of level of nesting is
allowed, but that should be sufficient for most use cases.
Note that by using the line continuation character "&", the if command
can be spread across many lines, though it is still a single
command:
can be spread across many lines, though it is still a single command:
if $a < $b then &
"print Minimum value = $a" &
if "$a < $b" then &
"print 'Minimum value = $a'" &
"run 1000" &
else &
"print Minimum value = $b" &
'print "Minimum value = $b"' &
"minimize 0.001 0.001 1000 10000" :pre
Note that if any executed comand is a bogus LAMMPS command, such as
"exit" in the first example above, then executing the command will
cause LAMMPS to halt.
Note that if one of the commands to execute is an invalid LAMMPS
command, such as "exit" in the first example above, then executing the
command will cause LAMMPS to halt.
Note that by jumping to a label in the same input script, the if
command can be used to break out of a loop. See the "variable
delete"_variable.html for info on how to delete the associated loop
variable, so that it can be re-used later in the input script.
delete"_variable.html command for info on how to delete the associated
loop variable, so that it can be re-used later in the input script.
Here is an example of a double loop which uses the if and
"jump"_jump.html commands to break out of the inner loop when a
@ -79,7 +96,7 @@ variable a loop 5
variable b loop 5
print "A,B = $a,$b"
run 10000
if $b > 2 then "jump in.script break"
if '$b > 2' then "print 'Jumping to another script'" "jump in.script break"
next b
jump in.script loopb
label break
@ -87,6 +104,52 @@ variable b delete :pre
next a
jump in.script loopa :pre
:line
The Boolean expressions for the if and elif keywords have a C-like
syntax. Note that each expression is a single argument within the if
command. Thus if you want to include spaces in the expression for
clarity, you must enclose the entire expression in quotes.
An expression is built out of numbers
0.2, 100, 1.0e20, -15.4, etc :pre
and Boolean operators:
A == B
A != B
A < B
A <= B
A > B
A >= B
A && B
A || B :pre
Each A and B is a number or a variable reference like $a or $\{abc\},
or another Boolean expression.
If a variable is used it must produce a number when evaluated and
substituted for in the expression.
Expressions are evaluated left to right and have the usual C-style
precedence: the 4 relational operators "<", "<=", ">", and ">=" have
the highest precedence; those 4 relational operators before the
remaining two relational operators "==" and "!="; those two relational
operators before the logical AND operator "&&"; and the AND operator
"&&" before the logical OR operator "||". Parenthesis can be used to
group one or more portions of an expression and/or enforce a different
order of evaluation than what would occur with the default precedence.
The 6 relational operators return either a 1.0 or 0.0 depending on
whether the relationship between x and y is true or false. The
logical AND operator will return 1.0 if both its arguments are
non-zero, else return a 0.0. The logical OR operator will return 1.0
if either of its arguments is non-zero, else return a 0.0.
The overall Boolean expression produces a TRUE result if the result is
non-zero. If the result is zero, the expression result is FALSE.
[Restrictions:] none
[Related commands:]

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@ -18,7 +18,8 @@
<P><B>Examples:</B>
</P>
<PRE>improper_style class2
improper_coeff 1 100.0 0
improper_coeff 1 100.0 0
improper_coeff * aa 0.0 0.0 0.0 115.06 130.01 115.06
</PRE>
<P><B>Description:</B>
</P>

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@ -15,7 +15,8 @@ improper_style class2 :pre
[Examples:]
improper_style class2
improper_coeff 1 100.0 0 :pre
improper_coeff 1 100.0 0
improper_coeff * aa 0.0 0.0 0.0 115.06 130.01 115.06 :pre
[Description:]

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@ -13,23 +13,23 @@
</H3>
<P><B>Syntax:</B>
</P>
<PRE>print str1 str2 ...
<PRE>print str
</PRE>
<UL><LI>str1,str2,...,strN = one or more text strings to print, which may contain variables
<UL><LI>str1 = text string to print, which may contain variables
</UL>
<P><B>Examples:</B>
</P>
<PRE>print Done with equilibration
print The system volume is now $v
<PRE>print "Done with equilibration"
print Vol=$v
print "The system volume is now $v"
</PRE>
<P><B>Description:</B>
</P>
<P>Print one or more text strings to the screen and logfile. The
individual text strings are effectively concatenated into a single
string, and one line of output is generated. Thus the 2nd and 3rd
examples above are equivalent. If variables are included in any of
the strings, they will be evaluated and their current values printed.
<P>Print a text string to the screen and logfile. One line of output is
generated. If the string has white space in it (spaces, tabs, etc),
then you must enclose it in single or double quotes so that it is
treated as a single argument. If variables are included in the
string, they will be evaluated and their current values printed.
</P>
<P>If you want the print command to be executed multiple times (with
changing variable values), there are 3 options. First, consider using

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@ -10,23 +10,23 @@ print command :h3
[Syntax:]
print str1 str2 ... :pre
print str :pre
str1,str2,...,strN = one or more text strings to print, which may contain variables :ul
str1 = text string to print, which may contain variables :ul
[Examples:]
print Done with equilibration
print The system volume is now $v
print "Done with equilibration"
print Vol=$v
print "The system volume is now $v" :pre
[Description:]
Print one or more text strings to the screen and logfile. The
individual text strings are effectively concatenated into a single
string, and one line of output is generated. Thus the 2nd and 3rd
examples above are equivalent. If variables are included in any of
the strings, they will be evaluated and their current values printed.
Print a text string to the screen and logfile. One line of output is
generated. If the string has white space in it (spaces, tabs, etc),
then you must enclose it in single or double quotes so that it is
treated as a single argument. If variables are included in the
string, they will be evaluated and their current values printed.
If you want the print command to be executed multiple times (with
changing variable values), there are 3 options. First, consider using

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@ -41,7 +41,7 @@
run 1000000 upto
run 100 start 0 stop 1000
run 1000 pre no post yes
run 100000 start 0 stop 1000000 every 1000 "print Protein Rg = $r"
run 100000 start 0 stop 1000000 every 1000 "print 'Protein Rg = $r'"
run 100000 every 1000 NULL
</PRE>
<P><B>Description:</B>
@ -120,7 +120,10 @@ number of arguments. Each of the trailing arguments is a single
LAMMPS command, and each command should be enclosed in quotes, so that
the entire command will be treated as a single argument. This will
also prevent any variables in the command from being evaluated until
it is executed multiple times during the run.
it is executed multiple times during the run. Note that if a command
itself needs one of its arguments quoted (e.g. the <A HREF = "print.html">print</A>
command), then you can use a combination of single and double quotes,
as in the example above.
</P>
<P>The <I>every</I> keyword is a means to avoid listing a long series of runs
and interleaving commands in your input script. For example, a
@ -161,10 +164,10 @@ command can be spread across many lines, though it is still a single
command:
</P>
<PRE>run 100000 every 1000 &
"print Minimum value = $a" &
"print Maximum value = $b" &
"print Temp = $c" &
"print Press = $d"
"print 'Minimum value = $a'" &
"print 'Maximum value = $b'" &
"print 'Temp = $c'" &
"print 'Press = $d'"
</PRE>
<P>If the <I>pre</I> and <I>post</I> options are set to "no" when used with the
<I>every</I> keyword, then the 1st run will do the full setup and the last

View File

@ -34,7 +34,7 @@ run 10000
run 1000000 upto
run 100 start 0 stop 1000
run 1000 pre no post yes
run 100000 start 0 stop 1000000 every 1000 "print Protein Rg = $r"
run 100000 start 0 stop 1000000 every 1000 "print 'Protein Rg = $r'"
run 100000 every 1000 NULL :pre
[Description:]
@ -113,7 +113,10 @@ number of arguments. Each of the trailing arguments is a single
LAMMPS command, and each command should be enclosed in quotes, so that
the entire command will be treated as a single argument. This will
also prevent any variables in the command from being evaluated until
it is executed multiple times during the run.
it is executed multiple times during the run. Note that if a command
itself needs one of its arguments quoted (e.g. the "print"_print.html
command), then you can use a combination of single and double quotes,
as in the example above.
The {every} keyword is a means to avoid listing a long series of runs
and interleaving commands in your input script. For example, a
@ -154,10 +157,10 @@ command can be spread across many lines, though it is still a single
command:
run 100000 every 1000 &
"print Minimum value = $a" &
"print Maximum value = $b" &
"print Temp = $c" &
"print Press = $d" :pre
"print 'Minimum value = $a'" &
"print 'Maximum value = $b'" &
"print 'Temp = $c'" &
"print 'Press = $d'" :pre
If the {pre} and {post} options are set to "no" when used with the
{every} keyword, then the 1st run will do the full setup and the last

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@ -332,9 +332,9 @@ relational operators "<", "<=", ">", and ">="; those 4 relational
operators before the remaining two relational operators "==" and "!=";
those two relational operators before the logical AND operator "&&";
and the AND operator "&&" before the logical OR operator "||".
Parenthesis can be used to group one or more portions of a formula and
enforce a different order of evaluation than what would occur with the
default precedence.
Parenthesis can be used to group one or more portions of a formula
and/or enforce a different order of evaluation than what would occur
with the default precedence.
</P>
<P>The 6 relational operators return either a 1.0 or 0.0 depending on
whether the relationship between x and y is true or false. For

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@ -331,17 +331,17 @@ relational operators "<", "<=", ">", and ">="; those 4 relational
operators before the remaining two relational operators "==" and "!=";
those two relational operators before the logical AND operator "&&";
and the AND operator "&&" before the logical OR operator "||".
Parenthesis can be used to group one or more portions of a formula and
enforce a different order of evaluation than what would occur with the
default precedence.
Parenthesis can be used to group one or more portions of a formula
and/or enforce a different order of evaluation than what would occur
with the default precedence.
The 6 relational operators return either a 1.0 or 0.0 depending on
whether the relationship between x and y is true or false. For
example the expression x<10.0 in an atom-style variable formula will
return 1.0 for all atoms whose x-coordinate is less than 10.0, and 0.0
for the others. The logical AND operator will return 1.0 of both its
for the others. The logical AND operator will return 1.0 if both its
arguments are non-zero, else return a 0.0. The logical OR operator
will return 1.0 of either of its arguments is non-zero, else return a
will return 1.0 if either of its arguments is non-zero, else return a
0.0. These relational and logical operators can be used as a masking
or selection operation in a formula. For example, the number of atoms
whose properties satifsy one or more criteria could be calculated by