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Homework Help: Permutations .How do u find the number of paths in a 3D object?

  1. May 3, 2005 #1
    Permutations....
    How do u find the number of paths in a 3D object?...let say a cube...from A to B....
     
  2. jcsd
  3. May 4, 2005 #2

    eax

    User Avatar

    I don't understand?

    maby you want the distance from A to B in 3D? Its the same formula as in 2D just an extra variable
    squareroot(x^2 + y^2 + z^2)

    assuming B is relative to A and those are B's cooridinates to A.

    Hope this helps!
     
  4. May 4, 2005 #3
    gillgill,
    It doesnt matter whether the object is 3D or 2D. What does matter is how many nodes and how are their interconnections. You can draw a 3D cube in a 2D way and calculate the number of paths from A to B without affecting anything. (All u have to make sure that u are representing every edge of 3D object in 2D diagram)

    -- AI
     
  5. May 4, 2005 #4
    how do u know how to draw it in 2D?...and from which point to which point?
     
  6. May 4, 2005 #5
    I'm also not sure where you're going with all of this. There's an infinite amount of paths between any two points in R^3, same thing with R^2. If you're talking about like, a lattice coordinate plane, this is different. A lattice coordinate plane only has "points" at integers, so it's actually feasible to count the number of paths between two points in a cube that is set in the lattice plane. If this is what you want (or if it isn't), please clarify.
     
  7. May 4, 2005 #6
    ...*--------*
    ../|.......... /|
    ./.|........../.|
    *--------*..|
    |..|.........|..|
    |..*------|--*
    |./..........|./
    |/...........|/
    *--------*

    Above i represent a cube in 2D (albeit in a very shabby way), but u would see that i have done 2D representation of the 3D cube and each node of the cube and each edge of the cube can be uniquely mapped to this figure.

    -- AI
     
    Last edited: May 4, 2005
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