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I need an examples really exist of a three dimensional array storage device.

Friday, July 30, 2004

Check out "The Tardis". It's multi-dimensional.

Friday, July 30, 2004

How many bits is that?

Li-fan Chen
Friday, July 30, 2004

I thought the inside of the Tardis wasn't in this dimension though, and so doesn't technically exist.

Matthew Lock
Friday, July 30, 2004

L- space. Ook.

Friday, July 30, 2004

Three dimesional arrays?

Man, even thinking about that sort of stuff will blow your mind!!!

Friday, July 30, 2004

Humm, all storage devices are physically three dimensional :)  However, most are logically one-dimensional, so why don't you come up with a mapping? If you want a 3x3x3, your just going to get an array[27] anyway.  You might as well just start that way.

Friday, July 30, 2004

People have difficulty visualising an array with more than three dimensions, apparently.

Think of it as a tree is often more natural.

i like i
Friday, July 30, 2004

>Think of it as a tree is often more natural.

How do you mean that?  I guess I don't see a good fit for a tree to an n-dimensional thing.  I can see a graph used for that purpose (you can make n-dimensional objects out of graphs anyway), but not necessarily a tree.

Friday, July 30, 2004

Technically a tree is just a specialized graph.  But who wants to split hairs?

Friday, July 30, 2004

I have a weird way of imagining mega-multi-dimensional arrays:

1-dimensional: line ---------------------

2-dim: graph

3-dim: cube

4-dim: line of cubes

5-dim: graph of cubes

6-dim: cube made out of cubes

7-dim: line of "cubes made out of cubes"

...and so on.

not convinced
Friday, July 30, 2004

I saw a picture of that in a textbook years ago and have been plagued with the same image...  Seems to work though.

Friday, July 30, 2004

"Cube made out of Cubes.." -- Isn't that a 'tessaract'?

(..And he built a crooked house.  Heinlein.)
(Also, A Wrinkle in Time.  Madeline L'Engle)

Friday, July 30, 2004

not convinced: nice. I do the same thing, and almost started to try to explain it, but my explanation would've been about 10 times as verbose.

Visualizing n-dim arrays is sure a heck of a lot easier than visualizing n-dim spaces. I remember having tried to take an arbitrarily-shaped (but simple) object and imagine rotating it through a fourth dimension -- had to stop before my brain exploded and made a big mess all over the room. Has anyone managed to think of a reasonable way to visualize n-dim objects that are not broken into finite, immobile chunks the way array slots are?

John C.
Friday, July 30, 2004

Doha -
As you've probably figured out, this is not the place to be asking that sort of question.  Try Google.

John C. -
I get to the "cube of cubes" stage and can image the inner cubes rotating around each other.  But beyond that, I totally lose it.

Guess I'm just not cut out to be a Time Lord.

Friday, July 30, 2004

Jimmy Jo-jo
Friday, July 30, 2004

Elephant, but that's the point -- it's a more restrictive form of graph than is most obvious for the n-dimensional 'visualization'.  By definition a tree can't contain cycles but, by definition, an n-dimensional space does have cycles.

1D is a graph like ('o' == node, '--' == edge):

... --o--o--o-- ...

So in 1D, each node has degree 2.  In 2D, each node has degree 4 (or 8 if you're into 2D cellular automata), and so on.  You can use this method to construct the elements of any n-dimensional space (but the space has to be discrete, as somebody else mentioned).

Saturday, July 31, 2004

I don't visualize arrays, I just see the dimensions as attributes: [city#][street#][street address][apartment wing#][floor#][room#] etc. There's six dimensions right there.

Saturday, July 31, 2004

About higher than 3 dimensions - a mathematician would probably tell you something along these lines:

'Visualising' higher-dimensional spaces in the conventional sense is hard/impossible for some - but if you think about them enough, about generalising various 2 or 3-dimensional problems to n dimensions, you end up looking past that and finding other ways of 'seeing' these spaces in a more abstract but equally valid way in your mind.

In short, if you look beyond the need to visualise things and really get your head round the idea of n-dimensional contructs from a formal/abstract point of view, in time you'll find yourself visualising them in a sense, just not the way you would have expected.

Visualising a 3-dim'l array should be a piece of piss though, just think about lots of little cubes arranged in a 3-dimensional grid.

Saturday, July 31, 2004

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