Date:         Wed, 3 Sep 2003 09:25:57 -0400
Reply-To:     Ian Whitlock <WHITLOI1@WESTAT.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Ian Whitlock <WHITLOI1@WESTAT.COM>
Subject:      Re: An efficiency question
Comments: To: "sashole@bellsouth.net" <sashole@bellsouth.net>
Comments: cc: "cjsadler@HOTMAIL.COM" <cjsadler@HOTMAIL.COM>
Content-Type: text/plain

Paul,

If Chris is really up against the wall on time, I would suggest that it is
time for you peek and poke magic.  Maybe use INDEX to search for "3244" etc.
If found then check if the index is at the beginning of a variable if not
then search from that point on until the begin point is grater than the
length of the relevant area.

IanWhitlock@westat.com

-----Original Message-----
From: Paul Dorfman [mailto:paul_dorfman@HOTMAIL.COM]
Sent: Wednesday, September 03, 2003 2:16 AM
To: SAS-L@LISTSERV.UGA.EDU
Subject: Re: An efficiency question


Chris,

You are searching sequentially but not stopping short when the condition is
satisfied and keep going all the way to i=30. This should improve the loop
performance about twice *on the average*:

  do i = 1 to 30 until ( flag1 and flag2 ) ;
    if _vars_(i) in ('3244','5664','6756') then flag1=1;
    if _vars_(i) in ('6546','4433') then flag2=1;
end;

Kind regards,
=================
Paul M. Dorfman
Jacksonville, FL
=================


>From: Christopher Sadler <cjsadler@HOTMAIL.COM>
>Reply-To: Christopher Sadler <cjsadler@HOTMAIL.COM>
>To: SAS-L@LISTSERV.UGA.EDU
>Subject: An efficiency question
>Date: Wed, 3 Sep 2003 01:56:35 +0000
>
>I have a dataset with a large number of variables that need to be evaluated
>to see if *any* of them fit into certain categories.   The way it's written
>now is shown in a simplified example below.   The problem is that the
>dataset is very large (3 million records, with many more to be added)
>and it
>takes a long time to run.   I suspect a major inefficiency with the code
>below is that do loop.  Is there a way to rewrite this to improve the
>processing speed?
>
>Thanks!
>Chris Sadler
>
>A simplified example:
>
>data new;
>set old;
>  array _vars_(30) var1-var30;
>
>  do i = 1 to 30;
>    if _vars_(i) in ('3244','5664','6756') then flag1=1;
>    if _vars_(i) in ('6546','4433') then flag2=1;
>end;
>
>run;
>
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