Usage:
cat xy.csv | sum-distinct
I use this script when counting the response times of a web service
per minute. Often I take the access logs, sed/awk/cut the time of
day and the milliseconds so that my "x" is the HH:MM and the "Y" is
the duration. When done, I have the total duration per minute
(sorted lexically).
It's perl as I often need to bring this to new servers which often
are "bare bones".