topic Re: Dynamically setting start and end variable in SAS Procedures

Dynamically setting start and end variable

brophymj — Tue, 03 Mar 2015 17:42:44 GMT

I have a dataset with 70 or so vehicle factors. My sas program is setup so that it takes each factors and creates a number of different graphs for analysis. I have the code working perfectly for one factor and I want to expand it to include all factors using a macro. I would rather not have to individually call each factor as follows:

%macro1(factor1);

%macro1(factor2);

%macro1(factor3);

%macro1(factor4);

...

%macro1(factor70);

In the data set the factors are listed under field "Factor". Is there a way of scanning this field, working out how many factors there are and then using a dynamic approach to achieving what I am trying to above.

In my head, this would work like this:

scan column

there are x factors

do I from 1st to last factor

%macro(i)

end

Re: Dynamically setting start and end variable

art297 — Tue, 03 Mar 2015 18:49:41 GMT

Possibly something like:

%macro macro1(factor);

proc print data=sashelp.class;

where sex eq "&factor.";

run;

%mend;

%macro driver;

proc sql noprint;

select distinct factor

into :factors

separated by ' '

from sashelp.class (rename=(sex=factor))

;

quit;

%do i=1 %to &sqlobs;

%macro1(%scan(&factors.,&i.));

%end;

%mend;

%driver

Re: Dynamically setting start and end variable

Reeza — Tue, 03 Mar 2015 19:01:40 GMT

Call execute works well for calling a macro multiple times:

data dates;

input date $;

datalines;

10nov97

11nov97

12nov97

;

data reptdata;

input date $ var1 var2;

datalines;

10nov97 25 10

10nov97 50 11

11nov97 23 10

11nov97 30 29

12nov97 33 44

12nov97 75 86

;

%macro rept(dat,a,dsn);

proc chart data=&dsn;

title "Chart for &dat";

where(date="&dat");

vbar &a;

run;

%mend rept;

data _null_;

set dates;

call execute('%rept('||date||','||'var1,reptdata)');

run;

Re: Dynamically setting start and end variable

Tom — Tue, 03 Mar 2015 21:38:04 GMT

When the number of values is reasonable then using SQL to build a macro variable is a useful way to do this, but note there is a limitation of 32,767 characters to a macro variable.

proc sql noprint ;

select distinct cats('%macro1(',factor,')')

into :mycode separated by ';'

from mytable

;

quit;

&mycode ;

Re: Dynamically setting start and end variable

Tom — Tue, 03 Mar 2015 21:42:01 GMT

Writing lines of code to a file to be included later is another method for dynamic code generation.

filename mycode temp ;

data _null_;

set mytable ;

by factor ;

file mycode;

if first.factor then put '%macro1(' factor= ');' ;

run;

%include mycode / source2 ;

Re: Dynamically setting start and end variable

data_null__ — Tue, 03 Mar 2015 21:59:33 GMT

I thought macro variables could be 65534. Guess I need to RTM.

Re: Dynamically setting start and end variable

Tom — Tue, 03 Mar 2015 22:16:37 GMT

I stand corrected.

2240 proc sql ;

2241 select x into :xx separated by ''

2242 from x

2243 where i<=1023

2244 ;

ERROR: The length of the value of the macro variable XX (65540) exceeds

the maximum length (65534). The value has been truncated to 65534

characters.

2245 %put %length(&xx);

65534