Date:         Thu, 8 Jun 2006 08:38:07 -0700
Reply-To:     chris@OVIEW.CO.UK
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         chris@OVIEW.CO.UK
Organization: http://groups.google.com
Subject:      Re: SAS date functions
Comments: To: sas-l@uga.edu
In-Reply-To:  <200606081344.k58CjB5o001361@mailgw.cc.uga.edu>
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Venky, the last Sunday in October can never be the 22nd  :-)

I was too slow, but here's my solution, avoiding the INTNX function,
which I've never used enough to be familiar with:

156  data _null_;
157    year = 2006;
158    lastsun = mdy(10, 31, year) - weekday(mdy(10, 31, year)) + 1;
159    put lastsun weekdate.;
160  run;

     Sunday, October 29, 2006

And a more tricksy version which avoids needing to know how many days
each month has:

219  data _null_;
220    month = 12;
221    year = 2006;
222
223    month = month + 1;
224    if month = 13 then do;
225      year = year + 1;
226      month = 1;
227    end;
228    lastsun = mdy(month, 1, year) - weekday(mdy(month, 1, year)) +
1;
229
230
231    put lastsun weekdate.;
232  run;

    Sunday, December 31, 2006

Chris.
--------------------------------------------------------
Elvis SAS Log Analyser - http://www.oview.co.uk/elvis
--------------------------------------------------------

Venky Chakravarthy wrote:
> On Thu, 8 Jun 2006 07:23:00 -0700, Paul <paulvonhippel@YAHOO.COM> wrote:
>
> >Are there convenient SAS functions for finding, say, the last Sunday in
> >October (which is the first day of daylight saving time)?
>
> Start in November and work backwards with INTNX. We can look for specific
> days of the week using week.1 for Sunday through week.7 Saturday. WEEK.1 is
> the default when you specify WEEK.
>
> 329  data _null_ ;
> 330    daylight = intnx ( "week" , "01NOV2006"d , -1 ) ;
> 331    put daylight= : weekdate. ;
> 332  run ;
>
> daylight=Sunday, October 22, 2006
>
> Venky Chakravarthy