Hi, Thank you for your answer. I want to do something slightly different now, and Im trying to do it with the code you provided, but since Im all new with this, the hashes and maps are a bit difficult to me.. I want to do it at a different order, because I want to do something else with it. I already combined multiple data files into one which now looks like this: 
cg12045430 43 16 6 44 23 63 24 77
cg12045430 43 16 6 44 23 63 24 80
cg12045430 43 16 6 44 23 63 24 45
cg12045430 43 16 6 44 23 115 24 77
cg12045430 43 16 6 44 23 115 24 80
cg12045430 43 16 6 44 23 115 24 45
cg12045430 43 16 6 44 23 29 24 77
cg12045430 43 16 6 44 23 29 24 80
cg12045430 43 16 6 44 23 29 24 45

[download]
So I have again the same id's on multiple lines and different values on columns 2-9. I want for one ID get the average of columns 2-9. So for that input file that would be: 
cg12045430 43 16 6 44 23 69 24 67

[download]
And afterwards I want to calculate the difference between column 2,3 and 4,5 and 6,7 and 8,9 like before. I tried to do it using your code and for every key calculate the average of the map, but it didn't work. Could you give me some advise? Thanks!

In reply to Re^2: compare values while value on other column remains the same by linseyr
in thread compare values while value on other column remains the same by linseyr

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