From: Tim Pollard <slinkyabc@...>
Date: 2010-01-23T04:45:30+09:00
Subject: Re: Sorting Method

Hi again,

Both of you were quite helpful in your explanations, and I think I
understand parameters and recursion a bit better now. I guess the
current hangup for me is trying to make these parameters applicable to
my sorting method. Also, I decided to try not to use global variables,
as I read that they are bad practice...but then I run into the problem
of not being able to call my arrays in my method.  Here is the code
again:

  def recursive_sort

  input = ['']
  unsorted_array = []
  sorted_array = []

    while not input.empty?
    input = gets.chomp
    unsorted_array.push input
    end
      if unsorted_array[0] < unsorted_array[1]
        sorted_array.push && unsorted_array.shift
      else
	unsorted_array.push (unsorted_array[1]) && unsorted_array.shift
      end
    puts sorted_array
end

recursive_sort

So I guess now my question is twofold: how do I include my initial
array assignments and the input = gets.chomp method without them
looping? I think I am starting to understand how to get the recursive
method as a WHOLE to stop, but I do not want the user to be able to
input more words every time the method calls itself, either. That is
why I was using global variables in the first place, but I suppose
there has to be a way to do it without...

Finally, using parameters to call the method: My initial problem was,
I suppose, that I expected parameters to be neatly defined. Using the
factorial example, method_factorial (n) just didn't make sense to me
because I thought that n would have to be a static number (rather than
whatever is written after method_factorial). So, I think that sheds
some light on my wrapper question too--by having a wrapper it would
allow me to call the recursive method with only one parameter instead
of two, correct?

I just don't understand what my program is supposed to do it I
arbitrarily write, say:

recursive_sort 418, 958

The parameters should be the arrays to be sorted, correct? I guess I'm
just not fully wrapping my head around the problem, and this message
is probably confusing, so I apologize. Just trying to understand it
fully. I think it is coming slowly, but I don't know why I'm having
such a difficult time with this.


Thanks for your initial responses, Robert and Jesús.

Regards,
Timothy