Practicum agenttechno 3

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Practicum agent-techno 3

• just some riddles

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riddle 1

• you must construct a given number out of four
  other numbers
• use addition, subtraction, multiplication, and
  division operations
• Each number must be used in the calculations
  exactly once
• multiple solutions are possible

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Example

• 42 out of 2, 3, 4 and 9
• Solution 1
• (9 x 4) (2 x 3)
• Solution 2
• ((9 x 2) - 4) x 3
• Solution 3
• (4 (2 / 3)) x 9
• 24 out of 1,3,4, and 6
• ...

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n queens problem
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Constraint staisfaction problem (CSP)

• consists of
• A finite set of variables, X X1, X2, ... ,Xn
• A domain set, containing a finite and discrete
  domain for each variable
• D D1, D2,..., Dn, ? i?1,n, Xi ? Di
• A constraint set, C C(R1), C(R2),... ,C(Rm),
  where each Ri is an ordered subset of the
  variables, and each constraint C(Ri) is a set of
  tuples indicating the mutually consistent values
  of the variables Ri.

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• n queens X X1, X2, ... ,Xn
• n x n chessboard D D1, D2,..., Dn,
• ?i, Di 1,2,...,n
• Placement requirement
• C C(Ru) ?i,j ? 1,n, C(Ru)
• ltb,cgtb ? Di, c ? Dj, b?c, i-j?b-c, i-j?c-b

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CSP-gtERA

• set of variables, X set of Agents, A
• domain set, D environment, E
• constraint set, C set of reactive rules, R

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initialisation
X1
X2
X3
X4
violation
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initialisation
X1
X2
X3
X4
violation
Place a1 at (3,1)
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initialisation
X1
X2
X3
X4
violation
Place a1 at (3,1)
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Moves

• Random move
• In the beginning
• When totally stuck
• Least move
• agent moves to minimum position
• if more than one make a choice
• Better move (not necessary)
• agent moves to random better position
• less efficient, but lower computational cost

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Moves
Random move
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Moves
Least move
Better move
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tips

• better-least-random move first try 'better
  move', if it doesn't found a solution (iidfas),
  try 'least move', iidfas, try 'random move'.
• make a sketch of your agent's communication
• does everyone has to move every step?
• if not, who moves?
• take care of computation time

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Communication

• start what happens?
• first step?
• step N to step N1?
• when is it finished?
• case M of ...then
• else Browse 'im programmed nonsens'
• end