topic Re: SAS not able to read data in SAS Programming

SAS not able to read data

Shravani0 — Fri, 24 Feb 2017 14:10:05 GMT

I have a dataset with the variable id and gcstot ( numerical score). Everytime I am trying to create a new variable using gcstot its giving me an error message that gcstot is uninitiated, even though its already there on the original dataset. The original dataset is as below. I am trying to run the code

data trs2;
gcs = gcstot*2;
run;

It is giving me the output as

gcstot gcs

Log:

Variable gcstot is uninitialized.

NOTE: Missing values were generated as a result of performing an operation on missing values.

Each place is given by: (Number of times) at (Line):(Column).

1 at 57:13

Dataset

obs id gcstot

-1

-2

Re: SAS not able to read data

nehalsanghvi — Fri, 24 Feb 2017 14:15:58 GMT

Your data step does not have a set statement which is required if you are trying to read in data from a certain dataset. The data statement specifies which dataset to *write* out to, it does not read data. This is what you need:

data trs2;
set trs2;
gcs = gcstot*2;
run;

Re: SAS not able to read data

Shravani0 — Fri, 24 Feb 2017 14:19:36 GMT

Thanks for your reply. But I have already done that in the previous data step.

Re: SAS not able to read data

jklaverstijn — Fri, 24 Feb 2017 14:19:55 GMT

Haha likely the title "SAS not able to read data" is the most tantalizing of all as that would be a first. In my 30 years of SAS that has not yet happened.

Luckily in this case it will also not happen 😉

What we see is a datastep where you forgot to refer to an input dataset. Now your variable gcstot was never given a value. The result makes sense: a missing value (the dot) for both gcstot and gcs.

I think you meant to code

data trs2;
set yourinput;
gcs = gcstot*2;
run;

When yourinput contains variable gcstot that will be read and the clculation will yield a non-missing value.

Regards Jan

Re: SAS not able to read data

nehalsanghvi — Fri, 24 Feb 2017 14:23:06 GMT

You have to specify a set statement every time you are trying to read a dataset (i.e. in each new data step). Not just once.

Re: SAS not able to read data

Shravani0 — Fri, 24 Feb 2017 14:29:30 GMT

Hi,

Thanks for your contribution. This is my SAS code what I am trying to run. I don't really see a problem with set statement here.

proc import out = triss1
datafile = "/home/srawanisarkar0/sasuser.v94/triss1.csv"
DBMS = csv replace;
getnames = yes;
run;

data trs1;
set triss1;
run;

proc means data = trs1;
var gcstot;

data trs2;
set trs1;
keep inc_key gcstot;
run;

data trs2;
gcs = gcstot*2;
run;

Regards,

shr

Re: SAS not able to read data

nehalsanghvi — Fri, 24 Feb 2017 14:30:46 GMT

Yes, you need a set statemenet in that last data step. Try ou the code I sent before:

set trs2;

Re: SAS not able to read data

nehalsanghvi — Fri, 24 Feb 2017 14:33:10 GMT

You can also combine the last two data steps into one, like this:

data trs2;
set trs1;
gcs = gcstot*2;
keep inc_key gcstot gcs;
run;

You do not need to do the calculation in a brand new data step.

Re: SAS not able to read data

Shravani0 — Fri, 24 Feb 2017 14:40:47 GMT

Great. Thanks! I didn't know I need a set statement everytime I use the dataset.

Re: SAS not able to read data

nehalsanghvi — Fri, 24 Feb 2017 14:47:08 GMT

In most data steps, you have to specify where your data should be read from and where it should be written out to (there are some exceptions like data _null_, but that is besides the point right now). The data statement only specifies where to *write* to, you need a set or an input statement to specify where to *read* the data from. No data to read in = no data to write out (unless you are generating data in that very data step).