compare two dataset

[SASUser0001]

hi I have two variables A and B . I wanted to compare those two variables based on date variable. on a particular date like 02/02/2019 if data is same then copy data before 02/0/2/2019 from A and 02/02/2/019 onwards  data from B and create new variable.

I am trying something like this.

data test;

set test_1;

length new_variable 8.;

if date='02FEB2019' then do;

if  A=B then new_variable = A;

end;

run;

[PaigeMiller]

Try this

if date='02FEB2019'D then do;

IIf that doesn' t fix the problem, then please explain the problem in a lot more detail, and please show us a portion of your data set.

[SASUser0001]

it bring data for that date but I wanted to bring all the data from this date. but it gives me only for that particular day record like one record.

29

30 data test

31 set test_1

32 length C 8.

33

34 if date='31APR2002'd then do

35 if A =B then C=A

36 end

run

so like following if A and b have same data on 30/04/2002 then before 30/04/2002 data comes from A and after 30/

date                A          B

28-Feb-02  1236    5842

31-Mar-02  5662   553

30-Apr-02   3526  3526

30-Jun-02 3525 2060

30-Sep-02 3524 2041

31-Dec-02 3523 2022

31-Mar-03 3522 2003

30-Jun-03 3521 1984

30-Sep-03 3520 1965

31-Dec-03 3519 1946

[SASUser0001]

and after 30/04/2002 comes from B and create variable C. sorry it didn't allow me to finish whole question in one

[PaigeMiller]

Please do NOT post code or log without semicolons. We have previously requested you not do this. Use the </> icon to post your log and use the "running man" icon to post code.

In your example, what should be done if A is not equal to B on the given date?

[SASUser0001]

sorry I didn't add semicolons as it gives me error when write message here.  if A=B then variable C should be created else c will be null. the way C should be created is before 30April2002 should come from A and after 30April2002 from B. thanks For helping

[s_lassen · Accepted solution]

I think what you want to do is something like this:

data test;
  set test_1;
  retain switch 0;
  if date='02FEB2019' and A=B then 
    switch=1;
  if switch then
    C=B;
  else
    C=A;
run;