SAS Macros

1. Macro Magic III
Macro Magic III
SAUSAG Presentation (30mins)

2. Overview
Overview

Macro Magic Posters have been displayed
at the last 2 SUGA presentations.

Continue the trend…

Hopefully everyone will learn something
new…

3. SAS Macro - Introduction
SAS Macro - Introduction

Used to generate (often repeated or
conditional) SAS code

4. SAS Macro - Introduction
SAS Macro - Introduction
proc print data=db.yr2000 noobs;
var month income expense;
run;
proc print data=db.yr2001 noobs;
var month income expense;
run;

5. SAS Macro - Introduction
SAS Macro - Introduction
%macro myprint(dset);
proc print data=&dset noobs;
var month income expense;
run;
%mend;
%myprint(db.yr2000)
%myprint(db.yr2001)

6. SAS Macro - Introduction
SAS Macro - Introduction
%macro myprint(dset);
proc print data=&dset noobs;
var month income expense;
run;
%mend;
%myprint(db.yr2000)
%myprint(db.yr2001)

7. SAS Macro - Introduction
SAS Macro - Introduction
%macro myprint(dset);
proc print data=&dset noobs;
var month income expense;
run;
%mend;
%myprint(db.yr2000)
%myprint(db.yr2001)

8. SAS Macro - Introduction
SAS Macro - Introduction
%macro myprint(dset);
proc print data=&dset noobs;
var month income expense;
run;
%mend;
%myprint(db.yr2000)
%myprint(db.yr2001)

9. SAS Macro - Introduction
SAS Macro - Introduction
%macro myprint(dset);
proc print data=db.yr2000 noobs;
var month income expense;
run;
%mend;
%myprint(db.yr2000)
%myprint(db.yr2001)
Executed
Code

10. Error Checking
Error Checking

Production SAS jobs should have error
checking

May need to run certain steps based on
failure

&syserr, &syslibrc, &sysfilrc, &syslckrc

0=success, +ve=error, -ve=warning

%goto

11. Error Checking
Error Checking
%macro update_db;
libname db "Q:DataFiles" access=readonly;
%if &syslibrc ne 0 %then %goto err_lib;
proc append base=db.invoices data=work.invoices;
run;
%if &syserr ne 0 %then %goto err_append;
%goto finish;

12. Error Checking
Error Checking
%err_lib:
%email_db("update_db: Library failure",admins);
%goto finish;
%err_append:
%email_db("update_db: Append failure",admins);
%goto finish;
%finish:
%mend update_db;

13. Error Checking
Error Checking

OPTIONS ERRORABEND; is a good
alternative, although has less control.

When an ERROR occurs, SAS will stop.

Beware this will close down an interactive
session unexpectedly!!!

14. Platform Checking
Platform Checking

&sysscp can be used to determine the
platform

Standard macro library for all platforms, with
occasional conditional code

%if &sysscp=WIN %then %do; …

%put &sysscp;

15. Platform Checking
Platform Checking
%macro myalloc(file);
%if &sysscp=WIN %then %do;
libname data "Q:Data&file"
access=readonly;
%end;
%else %if &sysscp=OS %then %do;
libname data "PROD.Q.&file..DATA"
disp=shr;
%end;
%mend myalloc;

16. Version of SAS Checking
Version of SAS Checking

Some installations may have more than one
version of SAS installed

%if &sysver=8.2 %then %do; …

17. Call Execute
Call Execute

Call Execute enables you to execute code
conditionally without macro

CALL EXECUTE(arg);

The argument is executed at the next step
boundary

18. Call Execute
Call Execute

19. Call Execute
Call Execute
%macro myprint(style);
proc print data=sasuser.houses;
title "Style of '&style'";
where style="&style";
run;
%mend myprint;

20. Call Execute
Call Execute
proc freq data=sasuser.houses noprint;
table style / out=work.styles;
run;

21. Call Execute
Call Execute
proc freq data=sasuser.houses noprint;
table style / out=work.styles;
run;

22. Call Execute
Call Execute
proc freq data=sasuser.houses noprint;
table style / out=work.styles;
run;
data _null_;
set work.styles;
call execute('%myprint('!!style!!');');
run;

23. Call Execute
Call Execute
67 data _null_;
68 set work.styles;
69 call execute('%myprint('!!style!!');');
70 run;
NOTE: There were 4 observations read from the data set ...
NOTE: CALL EXECUTE generated line.
1 + proc print data=sasuser.houses; title "Style of
'CONDO'"; where style="CONDO";
run;

24. Version 8 Enhancements
Version 8 Enhancements

%scan(argument,n<,delimiter>);

Now allows negative indexes
fullfile=d:DataBudget2001.xls
%let file=%scan(&fullfile,-1,);
file=2001.xls

25. Version 6 Goodies
Version 6 Goodies

%sysfunc(function(arg(s))<,format>);

Enables you to use standard SAS functions
not normally available to SAS Macros.
title "%sysfunc(date(),worddate.)";
title "July 24, 2002";

26. Version 6 Goodies
Version 6 Goodies

%sysfunc(function(arg(s))<,format>);

Enables you to use standard SAS functions
not normally available to SAS Macros.
%let date=%sysfunc(today());
title
"%sysfunc(intnx(MONTH,&date,0),date9.)";
title "01JUL2002";

27. Version 6 Goodies - %sysfunc
Version 6 Goodies - %sysfunc
%macro printds(dset);
%if %sysfunc(exist(&dset))=1 %then %do;
proc print data=&dset;
run;
%end;
%else
%put The data set &dset does not
exist.;
%mend printds;

28. Version 6 Goodies - %sysfunc
Version 6 Goodies - %sysfunc
SAS Functions Not Available with %SYSFUNC and
%QSYSFUNC
DIF DIM HBOUND
IORCMSG INPUT LAG
LBOUND MISSING PUT
RESOLVE SYMGET All Variable Information
Functions

29. Utility Macros
Utility Macros

Simple dataset locking without SAS/SHARE

%lock_dataset

%unlock_dataset

30. Utility Macros - Lock
Utility Macros - Lock
%macro lock_dataset(dsn);
%global lock_dataset_rc;
%let lock_dataset_rc = 0;
%let _max_attempts = 10;
%let _attempt = 0;
%check_exists:
%if %sysfunc(exist(&dsn)) ne 1 %then
%goto missing_dsn;
%lock_dataset:
lock &dsn;
%let rc = &syslckrc;

31. Utility Macros - Lock
Utility Macros - Lock
%if &rc ne 0 %then %goto try_again;
%goto finish;
%try_again:
lock &dsn clear;
%let _attempt = %eval(&_attempt + 1);
%if &_attempt eq &_max_attempts %then
%goto lock_error;
%if &_attempt ne &_max_attempts %then
%let rc = %sysfunc(sleep(1,1));
%goto lock_dataset;

32. Utility Macros - Lock
Utility Macros - Lock
%lock_error:
%let lock_dataset_rc = 10;
%goto finish;
%missing_dsn:
%let lock_dataset_rc = 20;
%goto finish;
%finish:
%mend lock_dataset;

33. Utility Macros - Unlock
Utility Macros - Unlock
%macro unlock_dataset(dsn);
%global unlock_dataset_rc;
%let unlock_dataset_rc = 0;
%check_exists:
%if %sysfunc(exist(&dsn)) ne 1 %then
%goto missing_dsn;
%unlock_dataset:
lock &dsn clear;
%let rc = &syslckrc;
%if &rc ne 0 %then %goto unlock_error;
%goto finish;

34. Utility Macros - Unlock
Utility Macros - Unlock
%unlock_error:
%let unlock_dataset_rc = 10;
%goto finish;
%missing_dsn:
%let unlock_dataset_rc = 20;
%goto finish;
%finish:
%mend unlock_dataset;

35. Macro Comments
Macro Comments

Don't forget to comment your code with:
/* Standard comment type 1 */
* Standard comment type 2 ;
%* Macro comments look like this ;

36. Conclusion
Conclusion

The SAS Macro Language is a powerful tool
for use with the SAS programming language

Hopefully the techniques presented will be
helpful in your own application development

37. References
References

SAS OnlineDoc
BASE SAS; SAS Macro Language Reference

SAS Institute Training
SAS Macro Language (2 Day)
Advanced SAS Macro Programming (2 Day)

http://www.sas.com

38. Macro Magic III
Macro Magic III
Questions???

39. Macro Magic III
Macro Magic III
Presentation available on our website:
http://www.qual-it.com.au
michael_matthews@qual-it.com.au