Shell Programming and Scripting

Hello

I have file that consist of 2 columns of millions of entries

timestamp and throughput

I want to find the average (throughput ) for each equal timestamp before change it to proper format

e.g : i want to average 2 coloumnd fot all 1308154800 values in column 1
and then
print 1308154800 with its average result
print 1308156600 with its average result
.
.
.
etc


sample file :

timestamp throughput
1308154800 7217
1308154800 353
1308154800 85
1308154800 35
1308154800 302
1308154800 778
1308154800 NA
1308154800 NA
1308154800 383
1308156600 4232
1308156600 10480
1308156600 10148
1308156600 2
1308156600 792608
1308156600 5362
1308156600 964
1308156600 10
1308156600 1666
1308156600 91
1308156600 NA
1308156600 0
1308156600 NA
1308156600 0
1308156600 729
1308156600 6
1308156600 34565
1308156600 5
1308156600 34
1308156600 0
1308156600 NA
1308156600 0
1308156600 0
1308156600 1375
1308156600 2087
1308156600 0
1308157200 NA
1308157200 134944
1308157200 NA
1308157200 647020
1308157200 NA

Thank you

Have a look here and here

Thank you h@ foorsa . biz

But :

I have i condition in my code

if or switch ( $1 is equal to next value in $1 )
( make an average for adjacent $2 )
then print timestamp value and average for specific timestamp
then go to next.

I've tried work with arrays but I could not do it

thank you

Code:

awk '{ T[$1] += $2; C[$1] ++; }
END { for (k in T) {  printf("%s\t%f\n",  k,T[k]/C[k]);    }'

Thank you very much Corona688