[ Thanks to Mike
Golvach for this link. ]
“The basic premise here is that you, I and the next guy
have all seen the solution to many a question like: “Given a file
filled with rows of space delimited numbers, how do I add up all
the values for field 2 ($2) in awk so that I can get the total when
awk is through processing my file?” …or something to that effect.
Knowing the fundamentals of performing arithmetic in awk can be a
great asset to you at work (or, at play, if you like to add,
subtract, multiply and divide for kicks ;), but, for the most part,
only the most banal instances of its application are either used or
queried for on the web (at least as far as my search engine testing
has shown so far).”