SAS PROGRAMMING
                                           HANDOUT #9
                                    SOME COMPLEX INPUT STATEMENTS


    There are several different DO loops possible in the SAS data step.
    The    @   symbol in this example is called a "trailing at-sign".  It holds a data line for the next
input statement in the step.
    This example is useful when one has a long list a data, and you only want to type in the Y-values
and have SAS generate the A, and B values

DATA TWO;
 DO A=1 TO 3;
  DO B=1 TO 2;
   INPUT Y @;
 OUTPUT; END; END;
CARDS;
1 2 3  4  5  6
7 8 9 10 11 12
PROC PRINT;
RUN;

   This example is very common, in the sense that you might receive data in this form.
   Again the   @   symbol  keeps the pointer when it was.
   Here the RETAIN statement keeps the value of the variables the same until a new value is assigned.
   Notice that depending on the value of TYPE different INPUTs are used.

DATA THREE;
 INPUT TYPE $ @ ;
  IF TYPE='C' THEN INPUT COURSE $ PROF $;
  RETAIN COURSE PROF;
  ELSE IF TYPE='S' THEN INPUT NAME $ SCORE;
CARDS;
C MATHSTAT RALESCU
S JIM 28
S BOB 47
S SARAH 100
C SASPROGRAMMING DEDDENS
S JIM 98
S BOB 65
etc
DATA TWO; SET ONE;
 IF TYPE='C' THEN DELETE;
PROC PRINT DATA=TWO;
RUN;

   This example is somewhat complicated and can be skipped.
   It illustrates RETAIN, and various DO's, IF-THEN's, and INPUT's in the data step

DATA FOUR;
 RETAIN CITY SNAME;
 INFILE CARDS;
 INPUT @1 CITY $ @;
 DO SPORT=1 TO 4;
   INPUT SNAME $ N  @;
   IF N=0 THEN DO; TEAMNAME='-----'; OUTPUT; END;
     DO J=1 TO N;
      INPUT TEAMNAME $ @;
     OUTPUT; END;
 END;
CARDS;
CINCY   BASEBALL   1 REDS   BBALL 0       HOCKEY 1 CLONES  FOOTBALLB 1 BENGALSG
CHICAGO   BASEBALL   2 CUBS WHSOX BBALL 1 BULLS HOCKEY 1 BHAWKS FOOTBALL 1 BEARS
;
PROC PRINT;
RUN;