OPTIONS LINESIZE=88 PAGESIZE=53 NOCENTER NODATE NONUMBER NOFMTERR;
*********************************************************************;
* Project name: Learn to use EPIINFO                                 ;
*     Program Name             Date            Programmer            ;
TITLE "Sourse:hw15.sas        12/01/99              CJ"              ;
* Description:  Soil ingestion studies are conducted to estimated the;
*   quantity of soil casually ingested by children and adults        ;
*********************************************************************;
LIBNAME new "C:\temp";

DATA food(drop=al0);     SET new.food;
     rename al_f=al_fd f_pid=Fd_pid;

DATA fecal(drop=al0);
     SET new.fecal;
     rename al_f=al_fl;

DATA soil(keep=al0 pidx);
     SET new.soil;


proc sort data=food;  by pidx;
proc sort data=fecal; by pidx;
proc sort data=soil;  by pidx;



**********************************;
*Q2. average daily amount of soil ;
*ingested for each subjects       ;
**********************************;

PROC sort data=new.d3;
     by pidx;

DATA new.d4;
   set new.d3;
   BY pidx;
   retain digest1 n 0;
   if digest ne . then do;
      digest1=digest1+digest;
      n=n+1;
    if last.pidx then do;
      rate=digest1/n;
      output;
      n=0;
      digest1=0;
    end;
   end;
label rate='average*daily*soil*digest*(mg)';

DATA new.d5(keep=pidx digest rate);
   set new.d4;


 proc print data=new.d5 split="*";
 Title2 "Table2. The average daily amount of soil ingested ";
run;