From: Michael Guterl <mguterl@...>
Date: 2008-11-02T02:03:19+09:00
Subject: Re: n-dimensional array in Ruby

On Sat, Nov 1, 2008 at 12:43 PM, Brian Adkins <lojicdotcom@gmail.com> wrote:
> Michael Guterl <mguterl@gmail.com> writes:
>
>> On Fri, Oct 31, 2008 at 8:09 PM, Christian <stadeschuldt@googlemail.com> wrote:
>>> Hi,
>>>
>>> i have a little Java problem, I want to solve using Ruby. Therefor I
>>> need an n-dimensional array. In Java it looks like this:
>>>
>>> double dArray[][][] = new double[x.length()+1][y.length()+1][x.length()
>>> +y.length()+3];
>>> dArray[0][0][0] = 0;
>>> dArray[0][0][1] = POSITIVE_INFINITY;
>>>
>>> Further values will be computed through loops and written into the
>>> array.
>>>
>>> How do I initialize such an array in Ruby?
>>>
>> Infinity = 1.0/0
>
> ~$ irb
> irb(main):001:0> X = 7
> => 7
> irb(main):002:0> Infinity = 1.0/0
> => Infinity
> irb(main):003:0> 0 / Infinity
> => 0.0
> irb(main):004:0> Infinity * Infinity
> => Infinity
> irb(main):005:0> Beyond = Infinity
> => Infinity
> irb(main):006:0> 2 * Infinity and Beyond
> => Infinity
> irb(main):007:0> Infinity.infinite?
> => 1
>
> Cool - I just learned about Infinity in Ruby. Hey Dave Thomas, maybe
> you could add a bit about Infinity in the next relase of Programming
> Ruby or Programming Ruby 1.9
>
Yeah, I don't think I've seen it discussed in any books before, but I
could be wrong.

I stumbled upon it accidentally one day when playing with ruby and
it's rules for division.

Michael Guterl