SAS PROGRAMMING
                                     HANDOUT #20

    This handout tries to illustrate various MACRO functions:

%LET     = assign a value to a macro variable

%EVAL    = evaluates arithmetic and logiscal expressions

%SYMPUT  = assigns a SAS variable value to a macro variable

%SYMGET  = assigns a macro variable value to a SAS variable

%SCAN    = scans for words in macro variable values

%STR     = used to surround character strings

LIBNAME JIM 'A:\';
OPTIONS MACROGEN MPRINT MLOGIC SYMBOLGEN;
DATA _NULL_;
 %LET Y=GNP;
 %LET A=RE;
 %LET B=G;
 %LET C=D;
 %LET E=F;
 %LET CF=INVEST;
DATA &Y.1; SET JIM.GNP;
PROC &A.&B;
 MODEL &Y=&&C&E;
 TITLE1 '1 &Y IS DEPENDENT VARIABLE';
 TITLE2 "2 &Y IS DEPENDENT VARIABLE";
RUN;


OPTIONS MACROGEN;
%MACRO JIM;
 %LET X=2;                           *creates a macro variable &X whose value is 2;
 %LET Y = %EVAL(&X+1);               *creates a macro variable &Y whose value is 3;

 DATA BOB;
  BB='BOB';
  SS='SET';
  NN=TRIM(LEFT(4));                  *this left justifies and then trims the blanks;
  CALL SYMPUT('NEW',NN);             *creates a macro variable &NEW whose value is 4;
  CALL SYMPUT('OLD',SS);             *creates a macro variable &OLD whose value is SET;
  CALL SYMPUT('NEWEST',SYMGET('OLD') || " " || BB);
                                     *creates a macro variable &NEWEST whose value is  SET BOB;
 PROC PRINT;  RUN;
 DATA DD&NEW;                        *NOTE try this without trimming and left justifying;
      &NEWEST;  F=1;
  RUN;

 %LET C=AB.CDE.FGHI.JKLMN;
 %LET D=%SCAN(&C,3,'.');           *creates a macro variable &D equal to the third "word";
                                   *delimited by commas, that is  FGHI;
 DATA D&D;
 %LET E=AB CDE FGHI JKLMN;
 %LET F=%SCAN(&E,2,%STR( ));       *creates a macro variable &F equal to the second "word";
                                   *delimited by spaces, that is CDE;
 %LET G=PROC SORT %STR(;) ;        /*creates a macro variable &G equal to PROC SORT;      */;
 %LET H=%STR(BY NN;) ;              /*creates a macro variable &H equal to BY NN;         */;
 DATA E&F; &NEWEST; &G &H          *notice there are no semi-colons after &G and &H;
%MEND;
%JIM;
RUN;