Week 11, Part 7: Macros for Repetitive Processing

This macro’s utility is in automation, dynamic processing, and safety.

• Dynamically loop over rows in a dataset
• Extract variables safely, even if they contain & or %
• Generate reports, filters, or custom SAS code for each row
• Avoid manual, repetitive coding

More specifically, the macro

• Takes a dataset (sashelp.class).

• Stores all rows in a single macro variable, using a safe delimiter (|) for columns and spaces for rows.

• Loops through each row (student) using macro logic.

• Extracts variables (name, sex, age) from each row.

• Each acts as row (e.g., prints a report for that student).

options nocenter nodate nonumber nosource symbolgen;
ods html close;

proc sql noprint;
  select catx('|', name, sex, age)
    into :student_list separated by ', '
  from sashelp.class;
quit;

%put %superq(student_list); /* safe display */
%put number of values: &sqlobs

The SAS System

NOTE: Writing HTML5(SASPY_INTERNAL) Body file: _TOMODS1
NOTE: PROCEDURE SQL used (Total process time):
      real time           0.00 seconds
      cpu time            0.00 seconds
      

Alfred|M|14, Alice|F|13, Barbara|F|13, Carol|F|14, Henry|M|14, James|M|12, Jane|F|12, Janet|F|15, Jeffrey|M|13, John|M|12, 
Joyce|F|11, Judy|F|14, Louise|F|12, Mary|F|15, Philip|M|16, Robert|M|12, Ronald|M|15, Thomas|M|11, William|M|15
SYMBOLGEN:  Macro variable SQLOBS resolves to 19
number of values: 19
The SAS System

E3969440A681A2408885998500000011

options nocenter nodate nonumber symbolgen;
ods html close;
%macro student_reports;
    %local i n obs name sex age;
    /* Count number of students */
    %let n = %sysfunc(countw(%superq(student_list), %str( )));
    %do i = 1 %to &n;
        /* Extract one student record */
        %let obs = %qscan(%superq(student_list), &i, %str( ));
        /* Parse name, sex, age */
        %let name = %qscan(&obs,1,|);
        %let sex  = %qscan(&obs,2,|);
        %let age  = %qscan(&obs,3,|);

        /* Dynamic report for this student */
        title "Report for &name (Sex: &sex, Age: &age)";
        proc print data=sashelp.class noobs;
            where name="&name";
        run;
    %end;
%mend;
%student_reports

Report for Alfred (Sex: M, Age: 14,)

Name	Sex	Age	Height	Weight
Alfred	M	14	69	112.5

---

Report for Alice (Sex: F, Age: 13,)

Name	Sex	Age	Height	Weight
Alice	F	13	56.5	84

---

Report for Barbara (Sex: F, Age: 13,)

Name	Sex	Age	Height	Weight
Barbara	F	13	65.3	98

---

Report for Carol (Sex: F, Age: 14,)

Name	Sex	Age	Height	Weight
Carol	F	14	62.8	102.5

---

Report for Henry (Sex: M, Age: 14,)

Name	Sex	Age	Height	Weight
Henry	M	14	63.5	102.5

---

Report for James (Sex: M, Age: 12,)

Name	Sex	Age	Height	Weight
James	M	12	57.3	83

---

Report for Jane (Sex: F, Age: 12,)

Name	Sex	Age	Height	Weight
Jane	F	12	59.8	84.5

---

Report for Janet (Sex: F, Age: 15,)

Name	Sex	Age	Height	Weight
Janet	F	15	62.5	112.5

---

Report for Jeffrey (Sex: M, Age: 13,)

Name	Sex	Age	Height	Weight
Jeffrey	M	13	62.5	84

---

Report for John (Sex: M, Age: 12,)

Name	Sex	Age	Height	Weight
John	M	12	59	99.5

---

Report for Joyce (Sex: F, Age: 11,)

Name	Sex	Age	Height	Weight
Joyce	F	11	51.3	50.5

---

Report for Judy (Sex: F, Age: 14,)

Name	Sex	Age	Height	Weight
Judy	F	14	64.3	90

---

Report for Louise (Sex: F, Age: 12,)

Name	Sex	Age	Height	Weight
Louise	F	12	56.3	77

---

Report for Mary (Sex: F, Age: 15,)

Name	Sex	Age	Height	Weight
Mary	F	15	66.5	112

---

Report for Philip (Sex: M, Age: 16,)

Name	Sex	Age	Height	Weight
Philip	M	16	72	150

---

Report for Robert (Sex: M, Age: 12,)

Name	Sex	Age	Height	Weight
Robert	M	12	64.8	128

---

Report for Ronald (Sex: M, Age: 15,)

Name	Sex	Age	Height	Weight
Ronald	M	15	67	133

---

Report for Thomas (Sex: M, Age: 11,)

Name	Sex	Age	Height	Weight
Thomas	M	11	57.5	85

---

Report for William (Sex: M, Age: 15)

Name	Sex	Age	Height	Weight
William	M	15	66.5	112

Macro-based automation

This approach is often used for:

• Batch reporting (one report per customer/row)
• Dynamic WHERE clauses
• Parameter-driven calculations

You can completely automate tasks without manually changing SAS code each time.