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***  GENERATE THE 4 FRACTIONS OF A 2**(6-2) DESIGN ***; 
***    DEFINING RELATION   I = ABCE = BCDF = ADEF  ***;
******************************************************;

DATA IN;
  DO F = -1 TO 1 BY 2; 
  DO E = -1 TO 1 BY 2; 
  DO D = -1 TO 1 BY 2; 
  DO C = -1 TO 1 BY 2; 
  DO B = -1 TO 1 BY 2; 
  DO A = -1 TO 1 BY 2; 

     DR1 = A*B*C*E;     DR2 = B*C*D*F; 

     IF DR1= 1 AND DR2= 1 THEN FRACTION=1;
     IF DR1=-1 AND DR2= 1 THEN FRACTION=2;
     IF DR1= 1 AND DR2=-1 THEN FRACTION=3;
     IF DR1=-1 AND DR2=-1 THEN FRACTION=4;  OUTPUT;

  END; END; END; END; END; END;

PROC SORT DATA=IN; BY FRACTION;
PROC PRINT DATA=IN; BY FRACTION;
     ID A B C D E F; VAR DR1 DR2;
TITLE 'USING SAS TO GENERATE A 2**(6-2) DESIGN';

RUN;