From: x1 <caldridge@...>
Date: 2006-10-12T11:52:19+09:00
Subject: Counting Frequency of Values in an Array (And Sorting by Frequency?)

Is there no method for an array that will tell me the # of occurrences
for an item?

IE:  ["a", "a", "a", "b", "c", "c"].count("a") #producing 3 ?

I almost thought that rindex would do the trick when looking at the
class docs but.. the example was just engineered to trick me  :-(

I realize I could pass these to a block and count but.. wanted to make
sure it didn't exist. If not, why? Thank you.. ( I did search btw.. no
avail )

Also, what's the best way of printing out each unique item and the
number of times it occurs, sorted by numerically by the number of
times it occurs?

IE: in my example above, i'd like to see (sorted by occurrence
greatest to least)
#desired output:
a: 3
c: 2
b: 1


Or sorted from least to greatest:
#desired output:
b: 1
c: 2
a: 3

I was able to hack it by using a hash doing various things to it.. but
it didn't seem "rubyish".

Thank you for any input.