Try this new modified version of the code, I have added a different city, so you can see how the code would behave with different time intervals, and you should be able to take it from here.....
 
data have;
    length    state $2
        city $10        
        fmtname $7
        start 8
        label $5
        hour 4
        minute 4;
    input state city fmtname start :date9. label hour minute;
    format start date9. label $5.;
    datalines;
MD Baltimore sunrise 17Jan2017 07:24 7 24
MD Baltimore sunset 17Jan2017 17:10 17 10
DE Dover sunrise 13JUL2017 04:47 4 47
DE Dover sunset 13JUL2017 19:28 19 28
;
run;
data want(drop=i);
    set have;
    array hours {24} 4 hour_0-hour_23;
    format hour_: BEST8.4;
    
    /* Set all Hours to 0 */
    do i=1 to dim(hours);
        hours[i]=1;
    end;
    if (fmtname='sunrise') then
        /* Assign the Subsequent Hours the factors (minutes/60) */
        do i=(hour+2) to (12+hour-1);
            hours[i]=minute/60;
        end;
    else if (fmtname='sunset') then
    do;
        /* Assign the Hours prior 8:00 am the factors (minutes/60) */
        do i=8 to 1 by -1;
            hours[i]=minute/60;
        end;
        /* Assign the Subsequent Hours the factors (minutes/60) */
        do i=(hour+2) to dim(hours);
            hours[i]=minute/60;
        end;
    end;
    output;
run;