What's the quickest way to get the mean of a set of numbers from the command line?

Question

Using any tools which you would expect to find on a nix system (in fact, if you want, msdos is also fine too), what is the easiest/fastest way to calculate the mean of a set of numbers, assuming you have them one per line in a stream or file?

Answer 1

Using "st" (https://github.com/nferraz/st):

$ st numbers.txt
N      min   max    sum    mean  sd
10.00  1.00  10.00  55.00  5.50  3.03

Specify an option to see individual stats:

$ st numbers.txt --mean
5.5

(DISCLAIMER: I wrote this tool :))

Answer 2

Awk

awk '{total += $1; count++ } END {print total/count}'

Answer 3

awk ' { n += $1 }; END { print n / NR }'

This accumulates the sum in n, then divides by the number of items (NR = Number of Records).

Works for integers or reals.

Answer 4

Using Num-Utils for UNIX:

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