Data Need ( Drop = Cnt LastDate ) ; Length Diff $ 2 ; Set Have ; By PROV_ID ID ;

LastDate = Lag( MyDate ) ;

If Not First.ID Then Do ; If MyDate Ne LastDate Then Do ; Cnt + 1 ; Diff = CatS( 'N' , Cnt ) ; End ; Else Do ; Diff = '0' ; End ; End ; Run ;

Toby Dunn "Don't bail. The best gold is at the bottom of barrels of crap." Randy Pausch

"Be prepared. Luck is where preparation meets opportunity." Randy Pausch

---------------------------------------- > Date: Tue, 8 Apr 2008 16:41:43 -0500 > From: tw2@MAIL.COM > Subject: Simple LAG Data Step > To: SAS-L@LISTSERV.UGA.EDU > > Hi everyone, > > The following problem looks like a simple LAG issue. > It doesn't work for me when I do a BY PROV_ID. > > I wish to create the DIFF variable as shown below. > > Thank you. > T > > > > PROV_ID ID MYDATE > 01 111111111 24Feb2003 > 01 111111111 24Feb2003 > 01 111111111 24Feb2003 > 01 111111111 24Feb2003 > > 02 222222222 24Sep2004 > 02 333333333 07Sep2003 > > 03 444444444 10Jul2003 > 03 444444444 03May2004 > 03 444444444 07Dec2005 > > > PROV_ID ID MYDATE DIFF > 01 111111111 24Feb2003 . > 01 111111111 24Feb2003 0 > 01 111111111 24Feb2003 0 > 01 111111111 24Feb2003 0 > > 02 222222222 24Sep2004 . /* or 0 doesn't matter*/ > > 02 333333333 07Sep2003 . /* or 0 doesn't matter*/ > > 03 444444444 10Jul2003 . > 03 444444444 03May2004 N1 > 03 444444444 07Dec2005 N2 > > N1= 03May2004 - 10Jul2003 > N2= 07Dec2005 - 03May2004 > > > > -- > Want an e-mail address like mine? > Get a free e-mail account today at www.mail.com!

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