topic Re: What function to use for multiple data set? in SAS Programming

What function to use for multiple data set?

jwill731 — Mon, 25 Jul 2016 03:59:37 GMT

Hi,

I'm analyzing data from year 2000 - 2015 with each year having its own data file. Instead of repeating all the procedures yearly, is there a shortcut function where I can analyze all the years with one code? I can try to merge all the files but each file contains around 80 million observations.

All the variables are the same for each year.

Thank you.

Re: What function to use for multiple data set?

Reeza — Mon, 25 Jul 2016 04:49:54 GMT

There isn't a function but you can create a macro. Macro in the simplest form generate code.

The macro below, called sample, runs proc means on the provided dataset. Note how the parameter is referenced within the macro (&datain).


Options MPRINT SYMBOLGEN;

%macro sample(datain);

Proc means data = &datain;
Run;

%mend;

%sample(sashelp.class);
%sample(sashelp.cars);

See a tutorial here:

http://www.ats.ucla.edu/stat/sas/seminars/sas_macros_introduction/

Re: What function to use for multiple data set?

AndrewHowell — Mon, 25 Jul 2016 04:50:14 GMT

Is your analysis "yearly", or are you performing the one analysis across all 15 years? Based on your request, I'm assuming the latter - if you want to avoid combining the tables first, you could instead create a view and then run the analysis on the view, although I'm not sure what your performance will be like.

Re: What function to use for multiple data set?

jwill731 — Mon, 25 Jul 2016 05:02:05 GMT

I am analyzing # of visits yearly rather than across 15 years.

For example.

# of visits in year 2000 = 1.3 million

# of visits in year 2001 = 1.4million

# of visits in year 2002 = 1.5 million

etc

I will be analyzing more than just # of visits but everything will be looked at yearly.

Re: What function to use for multiple data set?

jwill731 — Mon, 25 Jul 2016 05:04:00 GMT

Thank you. I think it's time for me to learn macro

Re: What function to use for multiple data set?

Kurt_Bremser — Mon, 25 Jul 2016 05:24:51 GMT

To run the statistics for each year, you can do

%macro stats;
%do year = 2000 %to 2015;
proc means data=mylib.data_&year;
.......
run;
%end;
%mend;
%stats;

Now, if you have the year in the dataset in a variable, you could do

%macro stats;
data work.statview/view=work.statview;
set
%do year = 2000 %to 2015;
  mylib.data&year
%end;
;
run;

proc means data=work.statview;
by yearvar;
.....
run;
%mend;
%stats;

Re: What function to use for multiple data set?

RW9 — Mon, 25 Jul 2016 08:18:39 GMT

As an alternative, you could do it in one simple datastep:

data tmp;
  do i=2000 to 2015;
    call execute(cats('proc means data=year_',i,'; var age; output out=yr',i,'; run;'));
  end;
  call execute('data want; set yr:; run;');
run;