Question

I have a topic in a forum where people can write their Top 10 List of songs. I want to count how many times a song is listed. The similarity has to be compared case insensitive.

Example of the file structure:

Join Date: Apr 2005
Location: bama via new orleans
Age: 48
Posts: 2,369
Re: Top 10 Songs Jethro Tull
oh dearrrr. the only way for all kaths to keep their last shred of sanity: fly through this list as quickly as possible, without stopping to think for a microsecond...
velvet green
dun ringill
skating away on the thin ice of a new day
sossity yer a woman
fat man
life's a long song
jack-a-lynn
teacher
mother goose
elegy

 03-10-2010, 02:29 AM      #5 (permalink)
Sox
Avoiding The Swan Song



Join Date: Jan 2010
Location: Derbyshire, England
Age: 43
Posts: 5,991
 Re: Top 10 Songs Jethro Tull
Wow !!!! Where do I start ?
Dun Ringill
Aqualung
With You There To Help Me
Jack Frost And The Hooded Crow
We Used To Know
Witch's Promise
Pussy Willow
Heavy Horses
My Sunday Feeling
Locomotive Breath

Join Date: Nov 2009
Posts: 1,418
 Re: Top 10 Songs Jethro Tull
Too bad they all can't make the list, but here's ten I never get tired of listening to:

Christmas Song
Witches Promise
Life's A Long Song
Living In The Past
Rainbow Blues
Sweet Dream
Minstral In The Gallery
Cup of Wonder
Rover
Something's On the Move

Example output:

life's a long song 3
aqualung 1
...

Answer 1

You’re file’s “structure” is a bit lacking in the structure department, so you’ll have to deal with some errors in the process.

Assuming you have all that in a file called input, try:

tr '[A-Z]' '[a-z]' < input | \
     egrep -v "^ *(join date|age|posts|location|re):" | \
     sort | \
     uniq -c

First line lowercases everything, second strips out the things that look like email headers in your sample, then sort and count unique items.