As Dale points out, arrays aren't really what you want here. They make the solution more complicated than it needs to be.

Jonathan Siegel

On Tue, 29 Jul 2003 11:46:03 -0700, Dale McLerran <stringplayer_2@YAHOO.COM> wrote:

>A simple datastep approach that works similarly to Prasad's SQL >solution would be as follows: > >data two; > set one(keep=vara rename=(vara=newvar)) > one(keep=varb rename=(varb=newvar)) > one(keep=varc rename=(varc=newvar)); >run; > > >An array based solution would have to load all of the data into >memory in a two dimensional array which is indexed on variable >and row number. When all data have been read, then loop back >through the data by row number within variable index. Thus, >we could write the following: > >data two; > set one end=lastrec; > array var_in {3} vara varb varc; > array all_dat {3,10000} _temporary_; > > /* Store observed values into _n_th row of all_dat array */ > do i=1 to 3; > all_dat{i,_n_}=var_in{i}; > end; > > /* Once we have read all the data, then loop over rows */ > /* within variable indexes and write the stored value. */ > if lastrec then do; > do i=1 to 3; > do j=1 to _n_; > newvar = all_dat{i,j}; > output; > end; > end; > end; > keep newvar; >run; > > >Hope these help, > >Dale > > >--- Prasad S Ravi <prasad.s.ravi@HOUSEHOLD.COM> wrote: >> Carey: >> >> If your friend does not care for a PROC SQL solution which may be >> less >> efficient than the array solutions >> here is another way, assuming the TYPE and LENGTH of the variables >> are the >> same: >> >> data one; >> vara=1; >> varb=2; >> varc=3; >> run; >> >> proc sql; >> create table two as >> select vara as newvar >> from one >> union >> select varb as newvar >> from one >> union >> select varc as newvar >> from one; >> quit; >> run; >> proc print data=two; >> run; >> >> output: >> >> Obs newvar >> 1 1 >> 2 2 >> 3 3 >> >> >> Prasad Ravi >> >> >> >> >> >> >> Carey Smoak >> <carey.smoak@ROCHE.CO To: >> SAS-L@LISTSERV.UGA.EDU >> M> cc: >> Sent by: "SAS(r) Subject: array >> processing >> Discussion" >> <SAS-L@LISTSERV.UGA.E >> DU> >> >> >> 07/29/2003 09:34 AM >> Please respond to >> Carey Smoak >> >> >> >> >> >> >> Hi SAS-Lers, >> >> I am submitting this question for a co-worker of mine. >> >> Suppose you have a dataset that has 10,000 observations and three >> variable (VarA, VarB and VarC). Suppose that you want to create a >> new >> dataset with a single variable that appends VarB and then VarC to >> VarA. This new dataset would have 30,000 observations. Is there a >> way to use array processing to accomplish this task? My co-worker >> has >> made several attempts at using arrays, but has not been successful. >> >> Of course, this can be done with several data steps, but my co-worker >> is trying to find a more efficient solution using arrays. >> >> Regards, >> >> Carey G. Smoak >> Roche Molecular Systems, Inc. > > >===== >--------------------------------------- >Dale McLerran >Fred Hutchinson Cancer Research Center >mailto: dmclerra@fhcrc.org >Ph: (206) 667-2926 >Fax: (206) 667-5977 >--------------------------------------- > >__________________________________ >Do you Yahoo!? >Yahoo! SiteBuilder - Free, easy-to-use web site design software >http://sitebuilder.yahoo.com