multi dimentional arrays?

RottenJalapeno

I was wondering if it is possible to make multidimentional arrays for variables?
What I am trying to do is have a list of 50 names (strings, 16 chars long), and have·information associated with each name,·that I can modify, and also index.
There might be an easier way to do this but I would think the easiest way would to through all the data into an array.
Any suggestions would be nice,
Thank you parallax, and all you parallaxers out there that helped me on several occasions
Jeremy

hippy

There are no multi-dimensional arrays as such but it is possible to 'fake them'.

Your 50 x 16 array is the same as a single array of 800 and you can replace all myArray[noparse][[/noparse]x,y] with myArray[noparse][[/noparse] x * 16 + y ]. You can also use helper methods to set and get array items ...

VAR
  byte myArray[noparse][[/noparse]800]

PUB Main | i

  i := Get_myArray(10,12)  ' myArray[noparse][[/noparse]1,1] := myArray[noparse][[/noparse]10,12]
  Set_myArray(1,1,i)

PRI Get_myArray(x,y)
  return myAray[noparse][[/noparse] x * 50 + y ]

PRI Set_myArray(x,y,value)
  myArray[noparse][[/noparse] x * 50 + y ] := value

Not perfect but possible workrounds.

Ken Peterson

You can also use an array of pointers to arrays. However, Hippy's suggestion is easier to implement in code and it is how multidimensional arrays are implemented "behind the scenes" anyway.

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RinksCustoms

The math behind a pseudo-3D array intrigues me, can anyone put it into laymans terms?

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E³ = Thought

http://folding.stanford.edu/·- Donating some CPU/GPU downtime just might lead to a cure for cancer! My team stats.

hippy

You mean as in "myArray[noparse][[/noparse]x,y,z]" ?

If so, for x = 0 to X, y = 0 to Y, z = 0 to Z

myArray[noparse][[/noparse] x * ( (Y+1)*(Z+1) ) + y * (Z+1) + z ]

( keeping my fingers crossed I've got that right )

Sapieha

Hi RinksCustoms.

hippy said..............
VAR
· byte myArray[noparse][[/noparse]800]

800 Linear bytes(X00000y00000y00000X00000y00000y00000X00000y00000y00000X00000y00000y00000X00000y00000y00000)
·You can break it in logic ARAY elements
X1 (X00000y00000y00000
X2 (X00000y00000y00000
X3 (X00000y00000y00000
X4 (X00000y00000y00000
X5 (X00000y00000y00000

etc....

PUB Main | i
· i := Get_myArray(10,12)· ' myArray[noparse][[/noparse]1,1] := myArray[noparse][[/noparse]10,12]
· Set_myArray(1,1,i)
PRI Get_myArray(x,y)
· return myAray[noparse][[/noparse] x * 50 + y ]
PRI Set_myArray(x,y,value)
· myArray[noparse][[/noparse] x * 50 + y ] := value

·

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Nothing is impossible, there are only different degrees of difficulty.
For every stupid question there is at least one intelligent answer.
Don't guess - ask instead.
If you don't ask you won't know.
If your gonna construct something, make it·as simple as·possible yet as versatile as posible.


Sapieha

Post Edited (Sapieha) : 9/30/2008 12:33:45 AM GMT

RinksCustoms

the only place i can think of that being useful is for a car engine emulator, or an RGB colorspace comparing program (like for matching a color to a databased color).

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E³ = Thought

http://folding.stanford.edu/·- Donating some CPU/GPU downtime just might lead to a cure for cancer! My team stats.

SRLM

multi dimensional arrays are useful in lots of places. Pretty much anywhere where you could use a table in a GUI, a multi array could store that data behind the scenes. Besides the obvious uses in coordinate systems, multi arrays could be used to store data such as temperature and humidity for each month(one axis in in units of months, the other is the two values, a 2x12 array), books on a bookshelf (number of shelves high x books wide x book cases back), or other interresting uses. Of course, if you have to make your own system, you'll probably have more mundane uses for the array.

RottenJalapeno

Thank you guys for your advice, I sort of thought thats what I would have needed to do. and I guess once it is down on paper it is easier than I first thought.
I really want to thank all of parallax for their free software, object exchange, and forums. They have helped me greatly in this project and the projects before. I am still learning a great deal during every project, and I hope one day I can put my 2 pennies back in the jar of knowledge. Thanks again parallax, you rock.