From: Ari Brown <ari@...>
Date: 2007-04-24T11:16:42+09:00
Subject: Re: [SPAM] Re: Shuffle Method


On Apr 22, 2007, at 11:15 PM, eden li wrote:
> Why not just do a random sort instead?
>>> some_array = ['cat', 'dog', 'fun', 'zoo']
> => ['cat', 'dog', 'fun', 'zoo']
>>> some_array.sort { rand(3) - 1 }
> => ["zoo", "dog", "fun", "cat"]

I wanted to write my own method to better understand how it works.  
Plus because it WAS fun, until it decided it didn't want to work.

P.S. = why rand(3) - 1? Why not just some other rand(x)?



>> --------------------------------------------------------------|
>> SOURCE 1
>> --------------------------------------------------------------|
>> some_array= ['cat', 'dog', 'fun', 'zoo']
>>
>> def shuffle some_array
>>    recurssive_shuffle some_array
>> end
>>
>> def recurssive_shuffle some_array
>>    n = some_array.length
>>    helper_array = []
>>    new_array = []
>>    while n != 0
>>      r = rand(n)
>>      while some_array.length != (r + 1)
>>        helper_array.push some_array.pop
>>      end
>>      new_array.push some_array.pop
>>      n = (n - 1)
>>      helper_array.each do |item|
>>        some_array.push item
>>      end
>>    end
>>    puts new_array
>> end
>>
>> shuffle some_array
>> --------------------------------------------------------------|
>> SOURCE 2
>> --------------------------------------------------------------|
>> some_array = ['cat', 'dog', 'fun', 'zoo']
>>
>> def shuffle some_array
>>    recurssive_shuffle some_array
>> end
>>
>> def recurssive_shuffle some_array
>>    n = some_array.length
>>    helper_array = []
>>    new_array = []
>>    while n != 0
>>      r = rand(n)
>>      while some_array.length != (r + 1)
>>        helper_array.push some_array.pop
>>        puts 'Array'
>>        puts helper_array
>>        puts
>>      end
>>      new_array.push some_array.pop
>>      n = (n - 1)
>>      helper_array.each do |item|
>>        some_array.push item
>>      end
>>    end
>>    puts new_array
>> end
>>
>> shuffle some_array
>>
>> ---------------------------------------------------------------|
>> ~Ari
>> "I don't suffer from insanity. I enjoy every minute of it" --1337est
>> man alive
>
>
>

---------------------------------------------------------------|
~Ari
"I don't suffer from insanity. I enjoy every minute of it" --1337est  
man alive