topic How to use a set of values from a macro variable(s) in SAS Programming

How to use a set of values from a macro variable(s)

yahoo0806 — Mon, 13 Dec 2021 17:01:20 GMT

Hi all,

I'm trying to write an iteration program and the main idea is that I want my program run multiple time and each time to use one value from a macro variable with a set of values.

The example code is as below:

data critlist;
input var1 var2;
datalines;
1.12 1.19
1.12 1.29
1.12 1.36
1.12 1.41
1.22 1.19
1.22 1.29
1.22 1.36
1.22 1.41
1.32 1.19
1.32 1.29
1.32 1.36
1.32 1.41
1.42 1.19
1.42 1.29
1.42 1.36
1.42 1.41
;

proc sql noprint;
select var1, var2 into :mvar1 separated by ' ', mvar2 separated by ' '
from critlist;
quit;

So my question is i don't know how to write my data step so that i can put the value from the macro variable into use:

data output; set input;

if ana_var > 1.12 *Here i don't know what to so that SAS will know if the the 1st value from &mvar1;

then ana_crit = "using 1.12"; *Here i don't know what to so that SAS will know if the the 1st value from &mvar1;

if ana_var > 1.19 *Here i don't know what to so that SAS will know if the the 1st value from &mvar2;

then ana_crit = "using 1.19"; *Here i don't know what to so that SAS will know if the the 1st value from &mvar2;

run;

then run this data step multiple times to use ALL values from &mvar1 and &mvar2.

so basically, i want to run my data step multiple times using each of the values i assigned to &mvar1 and &mvar2. But i don't know how to write the step....

Thanks!

Tina

Re: How to use a set of values from a macro variable(s)

ErikLund_Jensen — Mon, 13 Dec 2021 17:53:47 GMT

Hi Tina @yahoo0806

I cannot figure out what you are trying to achieve, so I might be totally wrong in my solution, but the code works as a demonstration of how one can loop over the mvar lists, take the next values and use them in a data step.

If I can be of any further help, please write back.

Erik

*The example code is as below:;

data critlist;
input var1 var2;
datalines;
1.12 1.19
1.12 1.29
1.12 1.36
1.12 1.41
1.22 1.19
1.22 1.29
1.22 1.36
1.22 1.41
1.32 1.19
1.32 1.29
1.32 1.36
1.32 1.41
1.42 1.19
1.42 1.29
1.42 1.36
1.42 1.41
;

data input (drop=i); /* For this example the input ds must end with a 0 (zero); */
	do i = 101 to 280 by 11;
		ana_var = i / 100;
		output;
	end;
run;

proc sql noprint;
select var1, var2 into :mvar1 separated by ' ', : mvar2 separated by ' '
from critlist;
quit;
%let loopcount = &sqlobs;

%let input = input; /* input dsname into macro variable */
%let outputprefix = out; /* prefix for numbered output ds */
%macro m;
	%do i = 1 %to &loopcount;
		%let thislow = %scan(&mvar1,&i,%str( ));
		%let thisuse = %scan(&mvar2,&i,%str( ));
		%put &=thislow &=thisuse;

		%if &i = 1 %then %let thisinput = &input;
		%else %let thisinput = &outputprefix%eval(&i-1);
		%put &=thisinput;

		data &outputprefix&i; set &thisinput;
			if ana_var > &thislow then ana_crit = catx(' ',"using","&thisuse");
		run;
	%end;
%mend;
%m;

Re: How to use a set of values from a macro variable(s)

PaigeMiller — Mon, 13 Dec 2021 18:07:10 GMT

Yes, please explain what you are trying to do here. I don't think you need macros at all, but then again, I don't understand the goal here.

Re: How to use a set of values from a macro variable(s)

Tom — Mon, 13 Dec 2021 18:44:01 GMT

If you have a list of value in a macro variable use %SCAN() to extract one of them.

%let i=1 ;
%put &=i %scan(&mvar1,&i,%str( ));

But why not just use your actual values instead of converting them from numbers into text and back again?

data output; 
  if _n_=1 then set crit (firstobs=&i obs=&i keep=var1 var2);
  set input;
  if ana_var > var1 then ana_crit = catx(' ','using',var1); 
  if ana_var > var2 then ana_crit = catx(' ','using',var2); 
run;