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Re: Where did the 3 geometric dimensions come from?

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ClutterFreak <ClutterFreak@fakeaddress.com> wrote:
> On Sat, 25 Jun 2016 22:44:24 -0000,
> jimp@specsol.spam.sux.com wrote:
> 
>> ClutterFreak <ClutterFreak@fakeaddress.com> wrote:
>>> On Fri, 24 Jun 2016 10:38:52 -0400, Michael J.
>>> Strickland wrote:
>>> 
>>>> We could easily number all locations in a cubical area with one
>>>> coordinate starting at top left, near and progressing to bottom, right
>>>> , far
>>> 
>>> I'm not sure but I think computers store 3-D
>>> information in that manner, using only one number to
>>> find various parts of it. 
>> 
>> Ummm, no, computers store 3D information in whatever manner the programmer
>> used, which could be anything. Generally it is in whatever is the easiest
>> convention for the task at hand.
>> 
>> The only computers I have ever heard of that knew anything about coordinates
>> were purpose built analog computers that used spherical coordinates. 
>> 
>> The task of locating a freeway off ramp is very different than the task
>> of defining an object for a 3D printer.
>> 
>> 
> 
> Again I'm not sure (this is very old stuff I'm trying
> to remember) but when you have, say, an array variable
> like A(i,j,k) with i going from 1 to 10, j from 1 to
> 100, and k from 1 to 5 computer allocates memory
> locations for it that form a continuous chain of 5000
> location (each for a different value of that
> variable). And when you want to retrieve what's stored
> at A(3,70,4) computer does 3 + 70*10 + 4*100 = 1103
> and goes to 1103rd position along that chain to get
> the value. It is similar to how Strickland wants to
> access a cubic volume using only one number. 
> 
> But I'm not sure :) 
> 
> Of course you could force the computer store your data
> in any strange way you want, but if you leave it to
> computer to do it that's I believe it does it.

How an array is stored is up to the compiler.

http://stackoverflow.com/questions/2565039/how-are-multi-dimensional-arrays-formatted-in-memory

https://en.wikipedia.org/wiki/Row-major_order


-- 
Jim Pennino

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Re: Where did the 3 geometric dimensions come from? Michael J. Strickland <michael06582@comcast.net> - 2016-06-24 10:38 -0400
  Re: Where did the 3 geometric dimensions come from? Sergio <invalid@invalid.com> - 2016-06-24 10:02 -0500
    Re: Re: Where did the 3 geometric dimensions come from? Michael J. Strickland <michael06582@comcast.net> - 2016-06-25 01:29 -0400
      Re: Where did the 3 geometric dimensions come from? Sergio <invalid@invalid.com> - 2016-06-25 15:01 -0500
    Re: Where did the 3 geometric dimensions come from? "Y.Porat" <y.y.porat@gmail.com> - 2016-06-26 01:04 -0700
  Re: Where did the 3 geometric dimensions come from? jimp@specsol.spam.sux.com - 2016-06-24 16:15 +0000
    Re: Where did the 3 geometric dimensions come from? benj <benj@nobody.net> - 2016-06-24 17:24 -0400
      Re: Where did the 3 geometric dimensions come from? jimp@specsol.spam.sux.com - 2016-06-24 22:03 +0000
        Re: Where did the 3 geometric dimensions come from? benj <benj@nobody.net> - 2016-06-24 18:25 -0400
          Re: Where did the 3 geometric dimensions come from? jimp@specsol.spam.sux.com - 2016-06-24 22:44 +0000
    Re: Re: Where did the 3 geometric dimensions come from? Michael J. Strickland <michael06582@comcast.net> - 2016-06-25 01:33 -0400
      Re: Where did the 3 geometric dimensions come from? jimp@specsol.spam.sux.com - 2016-06-25 15:44 +0000
        Re: Re: Where did the 3 geometric dimensions come from? Michael J. Strickland <michael06582@comcast.net> - 2016-06-26 15:34 -0400
          Re: Where did the 3 geometric dimensions come from? Sergio <invalid@invalid.com> - 2016-06-27 09:06 -0500
  Re: Where did the 3 geometric dimensions come from? ClutterFreak <ClutterFreak@FakeAddress.com> - 2016-06-25 16:45 -0500
    Re: Where did the 3 geometric dimensions come from? jimp@specsol.spam.sux.com - 2016-06-25 22:44 +0000
      Re: Where did the 3 geometric dimensions come from? noTthaTguY <abu.kuanysh05@gmail.com> - 2016-06-25 16:10 -0700
      Re: Where did the 3 geometric dimensions come from? ClutterFreak <ClutterFreak@FakeAddress.com> - 2016-06-25 18:25 -0500
        Re: Where did the 3 geometric dimensions come from? Sergio <invalid@invalid.com> - 2016-06-25 21:08 -0500
          Re: Where did the 3 geometric dimensions come from? ClutterFreak <ClutterFreak@FakeAddress.com> - 2016-06-25 21:58 -0500
          TripolarS from ... wTf are you from, any way noTthaTguY <abu.kuanysh05@gmail.com> - 2016-06-26 16:53 -0700
            Re: TripolarS from ... wTf are you from, any way noTthaTguY <abu.kuanysh05@gmail.com> - 2016-06-26 21:10 -0700
        Re: Where did the 3 geometric dimensions come from? jimp@specsol.spam.sux.com - 2016-06-26 02:04 +0000
          Re: Where did the 3 geometric dimensions come from? ClutterFreak <ClutterFreak@FakeAddress.com> - 2016-06-25 22:28 -0500
            Re: Where did the 3 geometric dimensions come from? jimp@specsol.spam.sux.com - 2016-06-26 04:49 +0000
              Re: Where did the 3 geometric dimensions come from? ClutterFreak <ClutterFreak@FakeAddress.com> - 2016-06-26 11:23 -0500
                Re: Where did the 3 geometric dimensions come from? jimp@specsol.spam.sux.com - 2016-06-26 17:33 +0000
                Re: Where did the 3 geometric dimensions come from? ClutterFreak <ClutterFreak@FakeAddress.com> - 2016-06-26 13:13 -0500

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