git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@11209 f3b2605a-c512-4ea7-a41b-209d697bcdaa

doc/Section_commands.html

@@ -100,19 +100,27 @@ single leading "#" will comment out the entire command.
 </P>
 <P>(3) The line is searched repeatedly for $ characters, which indicate
 variables that are replaced with a text string.  See an exception in
-(6).
+(6).  
 </P>
 <P>If the $ is followed by curly brackets, then the variable name is the
 text inside the curly brackets.  If no curly brackets follow the $,
 then the variable name is the single character immediately following
 the $.  Thus ${myTemp} and $x refer to variable names "myTemp" and
-"x". 
+"x".
 </P>
-<P>If the $ is followed by parenthesis, then the text inside the
+<P>How the variable is converted to a text string depends on what style
-parenthesis is treated as an "immediate" variable and evaluated as an
+of variable it is; see the <A HREF = "variable">variable</A> doc page for details.
-<A HREF = "variable.html">equal-style variable</A>.  This is a way to use numeric
+It can be a variable that stores multiple text strings, and return one
-formulas in an input script without having to assign them to variable
+of them.  The returned text string can be multiple "words" (space
-names.  For example, these 3 input script lines:
+separated) which will then be interpreted as multiple arguments in the
+input command.  The variable can also store a numeric formula which
+will be evaluated and its numeric result returned as a string.
+</P>
+<P>As a special case, if the $ is followed by parenthesis, then the text
+inside the parenthesis is treated as an "immediate" variable and
+evaluated as an <A HREF = "variable.html">equal-style variable</A>.  This is a way
+to use numeric formulas in an input script without having to assign
+them to variable names.  For example, these 3 input script lines:
 </P>
 <PRE>variable X equal (xlo+xhi)/2+sqrt(v_area)
 region 1 block $X 2 INF INF EDGE EDGE
@@ -148,14 +156,19 @@ 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 either double or single quotes.  E.g.
+it can be enclosed in either double or single quotes.  A long single
+argument enclosed in quotes can even span multiple lines if the "&"
+character is used, as described above.  E.g.
 </P>
 <PRE>print "Volume = $v"
-print 'Volume = $v' 
+print 'Volume = $v'
+variable a string "red green blue &
+                   purple orange cyan"
 if "$<I>steps</I> > 1000" then quit 
 </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 = "print.html">print</A> or
+</P>
+<P>See the <A HREF = "dump_modify.html">dump modify format</A> or <A HREF = "print.html">print</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). 

doc/Section_commands.txt

@@ -96,19 +96,27 @@ single leading "#" will comment out the entire command.
 
 (3) The line is searched repeatedly for $ characters, which indicate
 variables that are replaced with a text string.  See an exception in
-(6).
+(6).  
 
 If the $ is followed by curly brackets, then the variable name is the
 text inside the curly brackets.  If no curly brackets follow the $,
 then the variable name is the single character immediately following
 the $.  Thus $\{myTemp\} and $x refer to variable names "myTemp" and
-"x". 
+"x".
 
-If the $ is followed by parenthesis, then the text inside the
+How the variable is converted to a text string depends on what style
-parenthesis is treated as an "immediate" variable and evaluated as an
+of variable it is; see the "variable"_variable doc page for details.
-"equal-style variable"_variable.html.  This is a way to use numeric
+It can be a variable that stores multiple text strings, and return one
-formulas in an input script without having to assign them to variable
+of them.  The returned text string can be multiple "words" (space
-names.  For example, these 3 input script lines:
+separated) which will then be interpreted as multiple arguments in the
+input command.  The variable can also store a numeric formula which
+will be evaluated and its numeric result returned as a string.
+
+As a special case, if the $ is followed by parenthesis, then the text
+inside the parenthesis is treated as an "immediate" variable and
+evaluated as an "equal-style variable"_variable.html.  This is a way
+to use numeric formulas in an input script without having to assign
+them to variable names.  For example, these 3 input script lines:
 
 variable X equal (xlo+xhi)/2+sqrt(v_area)
 region 1 block $X 2 INF INF EDGE EDGE
@@ -144,13 +152,18 @@ 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 either double or single quotes.  E.g.
+it can be enclosed in either double or single quotes.  A long single
+argument enclosed in quotes can even span multiple lines if the "&"
+character is used, as described above.  E.g.
 
 print "Volume = $v"
-print 'Volume = $v' 
+print 'Volume = $v'
+variable a string "red green blue &
+                   purple orange cyan"
 if "${steps} > 1000" then quit :pre
 
 The quotes are removed when the single argument is stored internally.
+
 See the "dump modify format"_dump_modify.html or "print"_print.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