From: Todd Benson <caduceass@...>
Date: 2008-11-05T23:27:36+09:00
Subject: Re: String comparisions and counting

On Wed, Nov 5, 2008 at 8:18 AM, Brian Candler <b.candler@pobox.com> wrote:
> Stuart Clarke wrote:
>> I have an array full of strings which represent a date ID. The array
>> contains indivduals strings like the following:
>>
>> TueAug052008
>>
>> I want to iterate through this array (@eventbydate[]) and check each of
>> the values of the array. I then want a statement which says if any of
>> the date ID's in the array occurs more than 5 times print out some data.
>
>  counts = Hash.new(0)
>  @eventbydate.each { |e| counts[e] += 1 }
>  if counts.find { |c| c >= 5 }
>    puts "Print out some data"
>  end
>
> There are other variations:
>
>  ...
>  if counts.values.max >= 5
>  ...
>
> More efficient is to stop counting as soon as you reach 5, if you don't
> need the final values:
>
>  counts = Hash.new(0)
>  if @eventbydate.find { |e| (counts[e] += 1) >= 5 }
>    puts "Print out some data"
>  end
> --

Pretty darn good.  Why not use a database?  I guess it comes down to
often you want to query the data.

Todd