Re: st: merge within a range

[Phil Schumm <pschumm@uchicago.edu>]

On Sep 16, 2010, at 3:55 PM, Richard Goldstein wrote:
> I have the following merge problem. In one data set I have a start  
> date and and end date (and, of course, several other variables); in  
> another data set I have a particular date.  I want to merge the two  
> data sets with a match occurring if the "particular" date in data  
> set 2 is between (or equal) to the startdate/enddate in data set 1.
>
> An obvious kludge is to expand the first data set and fill-in the  
> dates to be consecutive.  If possible, however, I prefer not to do  
> this and am looking for any suggestions.


Merge by all of the other variables first, and then just drop the  
resulting observations that don't meet your condition (i.e., for which  
the date is not between your start and end).  If the other variables  
together do not uniquely identify the observations in either file,  
you'll need to use -joinby- instead of -merge-.


-- Phil

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