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help for ^swapval^ 
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Swapping values of two variables
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    ^swapval^ avar bvar { ^if^ exp | ^in^ list_of_obs } 


Description
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^swapval^ interchanges the values of avar and bvar, so long as both variables 
are numeric or both are string.   


Remarks
-------

^swapval^ may be useful whenever data checking suggests that values for two 
variables have been interchanged. In simple cases, this calls for a few 
^replace^ statements, or the use of the data editor (under Windows or 
Macintosh), but in other cases a single command may be useful. 

^swapval^ can be applied unconditionally, in which case it is in essence 

^tempname copy^   
^rename^ bvar ^`copy'^  
^rename^ avar bvar  
^rename `copy'^ avar 

Alternatively, it can be applied conditionally, using either ^if^ or ^in^, 
but not both. Note that ^in^ list_of_obs is more general than the usual ^in^ 
range. The list_of_obs can be any integer numlist specifying observation 
numbers, including numbers from ^1^ to _N or from ^-1^ to ^-^_N, provided 
that _N is replaced by the actual number. ^f^ and ^l^ for first and last 
observation are also indulged. 

Examples
--------

In a data set ^max^ should always be not less than ^min^. 
A check shows that this is not true in two observations, 
42 and 666. If we suppose that this must be a data error, 
then it can be fixed by 

 . ^swapval min max in 42 666^ 

or  

 . ^swapval min max if max < min^

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

	
Also see
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On-line:  help for @replace@, @edit@ (Windows or Macintosh) 

	

