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help for ^vallist^                                                 (STB-60: dm90)
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List distinct values of a variable
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    ^vallist^ varname [^if^ exp] [^in^ range] [, ^g^lobal^(^macname^) l^abels ^q^uoted 
                    [^no^]^t^rim ^m^ax^(^#^) w^ords ^f^ormat^(^format^) s^ep^(^string^) miss^ing]

Description
-----------

^vallist^ puts a sorted list of the distinct nonmissing values of varname,
which may be numeric or string, into local macro ^r(list)^ and displays 
that list. 

^vallist^ may be used interactively, but it is most likely to be useful to 
programmers dealing with categorical or counted data.


Remarks
-------

Stata itself trims leading spaces in any operation of the form 

     ^local^ macroname = string_variable[i] 

Trailing spaces are also trimmed by default. 


Options
-------

^global(^macname^)^ puts the list into global macro macname. 

^labels^ specifies that labels should be used for numeric variables with
    value labels.
    
^quoted^ specifies that values should be placed in ^" "^. This may be 
    useful for string values or value labels containing embedded spaces.
  
^notrim^ suppresses trimming of trailing spaces from string values.    
 
^max(^#^)^ specifies that at most, the first # characters of text (string
    values or value labels) should be used for each value. For example,
    ^max(8)^ may be needed to cut down text to elements acceptable in 
    Stata 6 as matrix row or column names.

^words^ specifies that text should be truncated to the first whole `word',
    that is, at just before the first space after a nonspace character. For
    example, a string value of ^"foo bar"^ would be represented by ^"foo"^.

^format(^format^)^ specifies a format for use. This is likely to be most 
    useful with noninteger numeric values. A string format should be 
    specified for string values or value labels and a numeric format 
    otherwise. 

^sep(^string^)^ specifies a separator other than a space, which is the
    default.
    
The sequence of operations is ^max()^, ^words^, ^format()^, ^sep()^.     

^missing^ specifies that missing values should also be listed. Missing 
    (i.e., empty) values of string variables are specified as ^"missing"^. 
    Note that this description may be truncated with the ^max()^ option. 

   
Saved results
-------------

^r(list)^ contains the list of distinct values.


Examples
--------

    . ^vallist rep78^
    . ^vallist rep78 if foreign, sep(,)^
    . ^vallist foreign, labels^

    . ^vallist mpg, s(,) g(vals)^
    . ^graph mpg, bin(10) xsc(0,50) xti($vals)^


Author
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         Nicholas J. Cox, University of Durham, U.K.
         n.j.cox@@durham.ac.uk


Acknowledgements 
----------------

	Fred Wolfe suggested that missing values be listable 
	and raised the problem of embedded spaces. 


Also see
--------

On-line: help for @tabulate@, @listutil@ (if installed) 
 Manual: ^[R] limits^