Date:         Sun, 10 May 2009 20:37:55 -0400
Reply-To:     Arthur Tabachneck <art297@NETSCAPE.NET>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Arthur Tabachneck <art297@NETSCAPE.NET>
Subject:      Re: keep value from previous iteration
Comments: To: Wensui Liu <liuwensui@GMAIL.COM>

Wensui,

Is the following all you are looking for?:

data have;
  input x;
  cards;
1
2
3
4
;

data want;
  set have;
  retain last_x;
  output;
  last_x=x;
run;

Art
---------
On Sun, 10 May 2009 20:25:22 -0400, Wensui Liu <liuwensui@GMAIL.COM> wrote:

>Dear All,
>I know it is relatively simple but just can't find an elegant and
>simple solution with retain statement.
>here is what I have.
>1
>2
>3
>4
>here is what i want
>1
>2 1
>3 2
>4 3
>
>I don't want to use lag() function or hash and just want to know a way
>in datastep with retain.
>thank you so much!
>--
>==============================
>WenSui Liu
>Acquisition Risk, Chase
>Blog   : statcompute.spaces.live.com
>
>Tough Times Never Last. But Tough People Do.  - Robert Schuller
>==============================