st: Re: looping through dates and keeping dates which are two years apart

["Michael Blasnik" <michael.blasnik@verizon.net>]

I think this should do what you want.

sort date
gen days=date-date[_n-1]
qui count if days<730
while r(N)>0 {
drop if days<730
replace days=date-date[_n-1]
qui count if days<730
}

Michael Blasnik
michael.blasnik@verizon.net

----- Original Message ----- 
From: "Rajesh Tharyan" <R.Tharyan@exeter.ac.uk>
To: <statalist@hsphsun2.harvard.edu>
Sent: Monday, February 27, 2006 5:18 AM
Subject: st: looping through dates and keeping dates which are two years 
apart


<snip>

> The logic of what I want to do is this..but I don't know how to code
> it..!!!!
>
> 1. Start with the first date.
>
> 2. See if the next date is more than 730 days from it. if its less than 
> 73o
> days away from the first date drop it.
>
> 3. If it is more than 730 days away keep it and
>
> 4. Now this date becomes the reference date and the difference between 
> this
> date and the next is calculated and so on
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