[ILUG] Perl thing of the day

[Fergal Daly]

I'm sure this exact piece of Perl has been written thousands of times by a
other people but I wrote it today and I think it's lovely

perl -pe 's/.*?(\d+)(.*)/"$2 ".("*" x $1)/ge'

will draw a histogram. It takes lines of the form

123 thing

and produces lines of the form

thing **********

where there are 123 *s

Got a list of usernames that have logged in over the last week?

sort list | uniq -c | perl -pe 's/.*?(\d+)(.*)/"$2 ".("*" x $1)/ge'

will graph them.

I had a bunch of account numbers generated by some unknown algorithm and I
wanted to know would it be good idea to to use the last 2 characters as a
hash. So I grabbed out the last two chars of each one and luckily enough

sort last_two | uniq -c | cut -f 1 | sort | uniq -c | perl -pe 's/.*?(\d+)(.*)/"$2 ".("*" x $1)/ge'

gave me a nice tight bell curve.

I love Perl :-)

Fergal