TITLE1 "P0102.SAS--Create file log's and post-pre diff log brightness";

LIBNAME INOUT01 "..\DATA\";

PROC SORT DATA=INOUT01.P0101
          OUT =ZERO;
BY ID TISSUE;

DATA ONE(RENAME=(LOGMEAN=PRELOG )) 
     TWO(RENAME=(LOGMEAN=POSTLOG ));
  SET ZERO;
IF ORDER=0 THEN OUTPUT ONE; *Grab the pre dose of contrast values;
           ELSE OUTPUT TWO; *post dose values;

DATA INOUT01.P0102;
LENGTH DEFAULT=4;
  MERGE ONE TWO;
        BY ID TISSUE;
  DIFFLOG=POSTLOG-PRELOG;
  KEEP ID TISSUE PRELOG POSTLOG TIME DIFFLOG;  
LABEL PRELOG ="log PRE contrst brghtnss"
      POSTLOG="log POST contrst brghtnss"
      DIFFLOG ="log post - log pre brghtnss";
FORMAT PRELOG POSTLOG 6.2 DIFFLOG 6.3;

PROC PRINT DATA=INOUT01.P0102 UNIFORM;