topic Re: Computing third variable using id and another variable in SAS Programming

Computing third variable using id and another variable

desireatem — Mon, 10 Nov 2014 18:22:30 GMT

Data A;

Imput id A;

Cards;

1 7

2 10

3 11

3 13

Run;

I want to create a variable B such
that

1 7 7-4=3

2 10 10-1=9

3 11 11-11=0(id=3)

3 13 13-11=2(id=3)

stat_sas — Mon, 10 Nov 2014 18:27:55 GMT

data want;

set A;

by id;

B=a-lag(a);

if first.id then B=0;

run;

Astounding — Mon, 10 Nov 2014 18:37:19 GMT

Not as well known, but equally effective here, is a cousin of the LAG function. These two statements produce identical results:

B=a-lag(a);

B=dif(a);