From: Sean Murphy <smurf_bp@...>
Date: 2008-01-14T18:00:03+09:00
Subject: Re: Two dimention arrays and accessing syslog.

Hi,

thanks for that, that was really cool code.

Regards
Sean Murphy
Skype: smurf20005

Life is a challenge, treat it that way.
----- Original Message ----- 
From: "Stefano Crocco" <stefano.crocco@alice.it>
To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
Sent: Monday, January 14, 2008 7:40 PM
Subject: Re: Two dimention arrays and accessing syslog.


Alle luned� 14 gennaio 2008, Sean Murphy ha scritto:
> All,
>
> A newby question, only been using Ruby for about 2 days.
>
> Is there a better way of creating a two dimention array, than the code 
> used
> below
>
> def create_world x, y
> row = Array.new
>
> y.times {
> |j|
> col = Array.new
> x.times {
> |i|
>
> map_type = rand(2)
> col[i] = map_type
> }
> row[j] = col
> }
>
> return row
> end
>
> world = create_world(gets.to_i, gets.to_i)

This should work:

def make_2d_array n_row, n_col
  Array.new(n_row) do
    Array.new(n_col){ rand(2) }
  end
end

make_2d_array(gets.to_i, gets.to_i)

The block form of Array.new creates an array of the size passed as argument,
then calls the block for each index of the array and stores the value
returned by the block in the corresponding element of the array (the block
can take one parameter, the index of the element, which wasn't necessary in
this case). See the ri documentation for Array.new for more information.

I hope this helps

Stefano