Method to create macro variables Open code using %let Inside a macro program Select into: in proc sql Call symput in data step
1. Open code: using %let The %LET statement enables you to define a macro variable and assign it a value %LET variable = value ; variable can be any name following SAS naming conventions value can be any string numeric tokens are stored as character strings, quotes are stored as part of the value the case of value is preserved
length range is 0-32K characters mathematical expressions are not evaluated leading and trailing blanks are removed from value before the assignment is made if variable already exists, value replaces the current value
1. Open code using %let
The following version of %LOOK uses the %LET to establish two global macro variables (&DSN and &OBS). %LET DSN = CLINICS; %LET OBS = 10; %MACRO LOOK; PROC CONTENTS DATA=&dsn; TITLE "DATA SET &dsn"; RUN; PROC PRINT DATA=&dsn (OBS=&obs); TITLE2 "FIRST &obs OBSERVATIONS"; RUN; %MEND LOOK; 2. Inside a macro program
%MACRO LOOK(dsn,obs); PROC CONTENTS DATA=&dsn; TITLE "DATA SET &dsn"; RUN; PROC PRINT DATA=&dsn (OBS=&obs); TITLE2 "FIRST &obs OBSERVATIONS"; RUN; %MEND LOOK; 2. Inside a macro program
2. Inside a macro program
%macro Count (var, var_label)
3. Select into: in proc sql 3) PROC SQL; SELECT … INTO: macrovariable …. ; proc sql noprint; select sum(amount) into:total from mydata; run; This defines a macro variable ‘total’ with a value that is the string representing the sum of variable ‘amount’ in SAS data set mydata
4. Call symput: in data step Store a value in a SAS macro variable
CALL SYMPUT (macro-variable, text); This creates a macro variable named ‘macrovariable’ with a value of ‘text’.
CALL SYMPUTN (unit, 100); This creates a macro variable named ‘unit’ with a value of 100.
