Compare values in an array and replace it if it's before the one previous.

[lei]

Hi i have an array called disch (*) disch1-disch9. 

I have a second array with empty values called dis_new(*) disch_new1-disch_new9. 

disch_new takes on the value of disch if its value is after the disch prior. However, if the disch value is before, then i want disch_new to take on the prior. Therefore, dischnew1-6 are the same as disch1-6. However, dischnew7-dischnew9 all become 26June18:10:00:00.

I am not having any luck with the way I have it set up. If anyone can help that will be great.

Current code is this: 

ARRAY DIS(*) DISCH1 - DISCH&IDY;
ARRAY DIS_NEW (*) DISCH_NEW1 - DISCH_NEW&IDY.;

DIS_NEW[1]=DIS[1];
DIS_NEW[2]=DIS[2];

/* If discharge date ends prior to previous discharge*/

DO I=2 TO DIM(DIS_NEW);
IF DIS_NEW[I]<DIS[I-1] THEN DIS_NEW[I]=DIS[I-1];
ELSe DIS_NEW[I]=DIS[I];
END;

[ChrisNZ]

Like this?

do I = 1 to DIM(DIS_NEW);
  DIS_NEW[I] = max( DIS_NEW[I-1], DIS[I] );
end;

[Patrick]

I believe for a DISCH_NEW<n> variable to never have a value lower than DISCH_NEW<n-1> the code @ChrisNZ posted needs a tweak. Below should do the job.

%let IDY=11;

data have;
  input DISCH1 - DISCH&IDY;
  datalines;
1 2 1 1 3 4 2 2 2 4 5
;

data want;
  set have;
  ARRAY DIS(*) DISCH1 - DISCH&IDY;
  ARRAY DIS_NEW (*) DISCH_NEW1 - DISCH_NEW&IDY.;
  DIS_NEW[1]=DIS[1];

  /* If discharge date ends prior to previous discharge*/
  DO I=2 TO DIM(DIS_NEW);
    IF DIS[I]<DIS_NEW[I-1] THEN
      DIS_NEW[I]=DIS_NEW[I-1];
    ELSe DIS_NEW[I]=DIS[I];
  END;
run;

proc print data=want;
run;