[SAS] problemi di codice

[ivand79]

Qualche genio di SAS sà spiegarmi queste righe di codice:

DATA NEW1;
     ARRAY PIP(&IND);
     SET TAB12(OBS=&IND) END=FINE;
     IF _N_=1 THEN I=1;
     ELSE I+1;
     PIP(I)=PERCENT;
     IF FINE THEN OUTPUT;
     RETAIN PIP1-PIP&IND;
/************************************/
DATA NEW2;
     ARRAY VX(&IND1) $ 20.;
     SET TAB1(OBS=&IND1) END=FINE;
     IF _N_=1 THEN I=1;
     ELSE I+1;
     VX(I)=VARX;
     IF FINE THEN OUTPUT;
     RETAIN VX1-VX&IND1;
/********************/
DATA NEW3;
     ARRAY VY(&IND2) $ 20.;
     SET TAB2(OBS=&IND2) END=FINE;
     IF _N_=1 THEN I=1;
     ELSE I+1;
     VY(I)=VARY;
     IF FINE THEN OUTPUT;
     RETAIN VY1-VY&IND2;
/********************/
   DATA VECT;
     SET NEW1;
     ARRAY  PIP{&IND};
     ARRAY  PIJ{&IND1,&IND2};
     K=1;
     DO I=1  TO &IND1;
          DO J=1  TO &IND2;
          PIJ{I,J}=PIP(K)/100;
          K=K+1;
     END;
     END;
     RETAIN PIJ1-PIJ&IND;
/**********************/

Grazie anticipatamente per qualsiasi aiuto.