Date: Wed, 22 May 1996 13:51:38 GMT
Reply-To: Zhongwen Lai <zwlai@LEXIS.POP.UPENN.EDU>
Sender: "SAS(r) Discussion" <SAS-L@UGA.CC.UGA.EDU>
From: Zhongwen Lai <zwlai@LEXIS.POP.UPENN.EDU>
Organization: University of Pennsylvania
Subject: Re: help of sum. in SAS programming
Some one posted a programming question (as follows) but I lost the after
I first quit the newgroup thus his/her name and email address. So I have
to post my answer to the group and hope he/she can read it.
Suppose there is a variable X in SAS data set Q, with its values denoted
as x1, x2, ..., xn from the first obs to the last obs n, how to
construct a new variable Y which is defined as follows:
x2 y2=x1+x2 (=y1+x2)
x3 y3=x1+x2+x3 (=y2+x3)
. . .
xn yn=x1+x2+,,,+xn (=y(n-1)+xn)
Y can also be expressed in the form of the third column, so the answer
This logic, in combination with FIRST.var and LAST.var, where var is the
variable by which the data is sorted (e.g, var is a ID variable for each
individual and each individual may have multiple obs in the data set),
you can also obtain the SUM of a given variable for each individual, or
simply count the number of occurences.
Zhongwen Lai at Upenn