topic if-then in SAS Programming

if-then

pchen002 — Wed, 27 Sep 2017 03:54:03 GMT

Given the raw data file EMPLOYEE:

----I----1 0---I----20---I----30
Ruth 39 11
Jose 32 22
Sue 30 33
John 40 44
The following SAS program is submitted:
data test;
infile ‘employee’;
input employee_name $ 1-4;
if employee_name = ‘Ruth’ then input idnum 10-11;
else input age 7-8;
run;
What value does the variable IDNUM contain when the name of the employee is “Ruth”?

Ans is 22? I do not understand why. Thanks

Re: if-then

Reeza — Wed, 27 Sep 2017 04:25:27 GMT

No trailing @.

Each INPUT statement reads from a new line by default. To keep it on the same line you need the trailing @.

Re: if-then

pchen002 — Wed, 27 Sep 2017 06:22:05 GMT

Sorry I still don't quite get it, still a noobie for SAS!!

Re: if-then

Shmuel — Wed, 27 Sep 2017 07:30:58 GMT

Compare next code to the one you used:

data test;
infile ‘employee’;
input employee_name $ 1-4  @;    /* <<<< @ added <<< */
if employee_name = ‘Ruth’ then input idnum 10-11;
else input age 7-8;
run;

You got 22 taken from next row.

The @ character makes sas stay on current row up to next INPUT ...; staement (without @).

Re: if-then

pchen002 — Wed, 27 Sep 2017 08:00:02 GMT

I understand the @ part already, but where do they start reading the data for idnum 10-11(not sure which column they read to result the observation=22)?

Re: if-then

error_prone — Wed, 27 Sep 2017 08:05:48 GMT

SAS reads from the columns you specified in
"then input idnum 10-11;"

Re: if-then

Shmuel — Wed, 27 Sep 2017 08:13:16 GMT

Having the code: "INPUT IDNUM 10-11;" means get idnum from positions 10-11.

Having "INPUT NAME 1-4 @"; you stay on current row with name=RUTH.

Without the @ character, sas skips to the next row where name=JOSE then

reads positions 10-11 with idnum=22;

Re: if-then

pchen002 — Wed, 27 Sep 2017 09:37:32 GMT

Understood!thanks!!