topic Re: Small macro for counter in SAS Programming

Small macro for counter

Bogdan — Thu, 18 Apr 2013 01:14:53 GMT

Question 1

If I write

data data1;

set data1;

count=_N_;

run;

then it works, but how do I do that with a macro?

I wrote

%_count (namedata);

data &namedata;

set &namedata;

count=_N_;

run;

%mend;

%_count(data1);

but it doesn't have effect (that is it does not create a count variable). I also added a "%let" or "%put" before "count" to no effect.

Question 2

I do that because I want to have a variable for the number of each observation. Is there a more direct way to extract the number of observation from dataset without creating a count variable ? I tried _N_, nobs, obs to no effect.

Re: Small macro for counter

SASKiwi — Thu, 18 Apr 2013 01:41:40 GMT

You are missing the macro keyword:

%macro _count (namedata);

data &namedata;

set &namedata;

count=_N_;

run;

%mend;

%_count(data1);

Re: Small macro for counter

Bogdan — Thu, 18 Apr 2013 01:50:21 GMT

yes, but it's more than that

Re: Small macro for counter

andreas_lds — Thu, 18 Apr 2013 07:41:51 GMT

I don't see an easier way to move the observation counter to a variable. Way do you need the counter?

Re: Small macro for counter

Bogdan — Thu, 18 Apr 2013 07:48:58 GMT

I need it in general, but in the particular case today was in order to plot a variable and I needed the x axis values (which is the observation number)

Re: Small macro for counter

LinusH — Thu, 18 Apr 2013 08:31:40 GMT

SASKiwi has the answer to Q1.

Q2: It would be great if the observation number were available as an automaic variable throughout SAS, but it isn't. It's available within the data step with _n_ as you already know, and i SQL using the montonic() function. So if you need to do reports based on observation no, you need to store it explicitly.

Re: Small macro for counter

Ron_MacroMaven — Thu, 18 Apr 2013 21:25:30 GMT

There is a macro function named Nobs that uses SCL code to open and close the data set

and return the Nobs(data).

usage:

%Let Nobs = %nobs(data=sashelp.class);

%put note nobs:&Nobs;

http://www.sascommunity.org/wiki/Macro_Nobs_function

Ron Fehd macro fun. maven

Re: Small macro for counter

Peter_C — Thu, 18 Apr 2013 21:47:45 GMT

there is a little-used part of SAS that provides the row-number

Have a look at the function CUROBS()

In SAS/AF it needs a dataset-id number parameter but needs no parameter in SAS/FSP (presumeably because the facilities in FSP address just one table at a time)

Re: Small macro for counter

Reeza — Thu, 18 Apr 2013 21:53:27 GMT

That seems like a very non-standard way to store your data.

Can you explain more about what you're trying to do overall?

Re: Small macro for counter

Bogdan — Sat, 20 Apr 2013 18:03:03 GMT

I had the word "macro" only forgot to write it when the question was posted. I tried again and this time it worked. I don't why it didn't work first time.