Hello,

I request your kind help in solving this problem...

I have a file with two columns and "n" number of rows. For the first column, it won't be change. For the second column, I want to take the average of the first three rows. Then assign the averaged value to the first three rows. This process will be applied as well to the following 3 rows, after the changed rows. The output file will have two columns, the unchanged column ($1) and the changed column ($2). To illustrate the problem...

Input file:
$1= 1, 2, 3, 4, 5, 6.....n
$2= 2, 4, 6, 8, 10, 12....n

Output file:
$1= no change
$2= 4, 4, 4, 10, 10, 10....n (average of 2,4,6 is 4. average of 8,10,12 is 10)

So far I have an AWK code that doesn't work:
BEGIN {a[NR]=$2}
{
for (i=1;i<=n;i++) {
avg=(a[i]+a[i+1]+a[i+2])/3;
a[i]=avg;
a[i+1]=avg;
a[i+3]=avg;
i=i+4;
};
}
END {
i=1;
while (i<=n) {print $1, a[i]; i+=1;};
}

I'll appreciate a lot your help!

Solracq