Game strategies from week 1 2022

[olufjen]

An Action Schema is applicable if the preconditions are satisfied by the initial state.
(see p. 368)
In addition, for the search algorithm to return with a plan then the fluents of the goal state must all be present among the fluents of the outcome. As shown on p. 369:
The problem is solved when we can find a sequence of actions that end in a state s that entails the goal.
This is expressed in the sentence:
if (outcome.getFluents().containsAll(problem.getGoalState().getFluents())) {
In the Chess Search Algorithm.

Make sure that an Action Schema contains a PROTECTED precondition in order to be chosen.
There is an initial and goal state for every action schema and chess action available.
If the chess search algorithm does not return with a plan, try again with another Chess Problem with a different initial and goal state?

[olufjen]

When moving White Bishop 2 to d3:
Chosen action Schema
Action(WhiteBishop2)
PRECOND:^occupies(WhiteBishop2,f1)^PIECETYPE(WhiteBishop2,BISHOP)
EFFECT:^occupies(WhiteBishop2,c4)^PIECETYPE(WhiteBishop2,BISHOP)

Chosen action
ChessAction: Preferred Position d3 Piece Piece position f1 X, Y (5, 0) wB f1 BISHOP ActiveName B

Possible move Move
Piece Piece position f1 X, Y (5, 0) wB f1 BISHOP ActiveName B
From position f1 Color W Direction NONE sumdif 5 Piece no.chess.web.model.ChessPiece Ontology name WhiteBishop2
Chesspiece position f1
Piece active: true true Friendly false gamepiece null

To position c4 Color W Direction NONE sumdif 6 Piece None false Friendly false gamepiece Gamenone
Move number 0
Creation Created from gamepiece preferred position

[olufjen]

The following game:

Chosen action Schema
Returning with a reserve plan. Then the first action schema is chosen.
Action(WhitePawn3)
PRECOND:^occupies(WhitePawn3,c4)^PIECETYPE(WhitePawn3,PAWN)
EFFECT:^occupies(WhitePawn3,d5)^PIECETYPE(WhitePawn3,PAWN)
The new position and the preferred position
d5
d5
The fluents of the init state
occupies(WhitePawn3,c4)
BOARD(c4)
PIECETYPE(WhitePawn3,PAWN)
REACHABLE(WhitePawn3,c5)
BOARD(c5)
PROTECTEDBY(WhitePawn4,c5)
The fluents of the goal state
occupies(WhitePawn3,d5)
PIECETYPE(WhitePawn3,PAWN)
BOARD(d5)
The Chess search algorithm returns with a reserve plan with the above setting.
Compare with original:
Chosen action Schema
Action(WhitePawn3)
PRECOND:^occupies(WhitePawn3,c4)^PIECETYPE(WhitePawn3,PAWN)
EFFECT:^occupies(WhitePawn3,c5)^PIECETYPE(WhitePawn3,PAWN)
Returns with a plan: The fluents of end outcome:

occupies(WhitePawn3,c4)
BOARD(c4)
PIECETYPE(WhitePawn3,PAWN)
REACHABLE(WhitePawn3,c5)
BOARD(c5)
PROTECTEDBY(WhitePawn4,c5)
occupies(WhitePawn3,c5)
PIECETYPE(WhitePawn3,PAWN)
occupies(WhitePawn3,c5)
PIECETYPE(WhitePawn3,PAWN)
The fluents of goal state:

occupies(WhitePawn3,c5)
PIECETYPE(WhitePawn3,PAWN)
BOARD(c5)

The initial state is "wrong" because it uses the symbolic name REACHABLE !!!

[olufjen]

When Problem is created:
The fluents of the init state
occupies(WhitePawn3,c4)
BOARD(c4)
PIECETYPE(WhitePawn3,PAWN)
REACHABLE(WhitePawn3,c5)
BOARD(c5)
PROTECTEDBY(WhitePawn4,c5)

The fluents of the goal state
occupies(WhitePawn3,c5)
PIECETYPE(WhitePawn3,PAWN)
BOARD(c5)

And then when it returns with a plan from the Chess Search algorithm::

Returns with a plan: The fluents of end outcome:

occupies(WhitePawn3,c4)
BOARD(c4)
PIECETYPE(WhitePawn3,PAWN)
REACHABLE(WhitePawn3,c5)
BOARD(c5)
PROTECTEDBY(WhitePawn4,c5) --- These lines are added:
occupies(WhitePawn3,c5)
PIECETYPE(WhitePawn3,PAWN)
occupies(WhitePawn3,c5)
PIECETYPE(WhitePawn3,PAWN)
The fluents of goal state:

occupies(WhitePawn3,c5)
PIECETYPE(WhitePawn3,PAWN)
BOARD(c5)

[olufjen]

Reserve plan for castling:

The fluents of end outcome:

occupies(WhiteKing,e1)
BOARD(e1)
PIECETYPE(WhiteKing,KING)
REACHABLE(WhiteKing,f1)
BOARD(f1)
REACHABLE(WhiteKing,e2)
BOARD(e2)
REACHABLE(WhiteKing,d2)
BOARD(d2)
PROTECTEDBY(WhiteBishop2,f1)
PROTECTEDBY(WhiteBishop2,e2)
PROTECTEDBY(WhiteKnight1,e2)
PROTECTEDBY(WhiteKnight2,d2)
PROTECTEDBY(WhiteBishop1,d2)
PROTECTEDBY(WhiteRook2,f1)
PROTECTEDBY(WhiteQueen,d2)
PROTECTEDBY(WhiteQueen,e2)
The fluents of goal state:

occupies(WhiteKing,g1)
PIECETYPE(WhiteKing,KING)
BOARD(g1)

End chess search with a reserve plan

And from the problem planning phase:
Chosen action Schema
Action(WhiteKing)
PRECOND:^PROTECTEDBY(WhiteKnight2,g1)^PROTECTEDBY(WhiteRook2,g1)^occupies(WhiteKing,e1)^PIECETYPE(WhiteKing,KING)
EFFECT:^occupies(WhiteKing,g1)^PIECETYPE(WhiteKing,KING)
The new position and the preferred position
g1
g1
The fluents of the init state
occupies(WhiteKing,e1)
BOARD(e1)
PIECETYPE(WhiteKing,KING)
REACHABLE(WhiteKing,f1)
BOARD(f1)
REACHABLE(WhiteKing,e2)
BOARD(e2)
REACHABLE(WhiteKing,d2)
BOARD(d2)
PROTECTEDBY(WhiteBishop2,f1)
PROTECTEDBY(WhiteBishop2,e2)
PROTECTEDBY(WhiteKnight1,e2)
PROTECTEDBY(WhiteKnight2,d2)
PROTECTEDBY(WhiteBishop1,d2)
PROTECTEDBY(WhiteRook2,f1)
PROTECTEDBY(WhiteQueen,d2)
PROTECTEDBY(WhiteQueen,e2)
The fluents of the goal state
occupies(WhiteKing,g1)
PIECETYPE(WhiteKing,KING)
BOARD(g1)

[olufjen]

The problem of the previous comment is solved:

From the scheduling phase, we get this action schema and its initial and goal states:
Chosen action Schema
Action(WhiteKing)
PRECOND:^PROTECTEDBY(WhiteKnight2,g1)^PROTECTEDBY(WhiteRook2,g1)^occupies(WhiteKing,e1)^PIECETYPE(WhiteKing,KING)
EFFECT:^occupies(WhiteKing,g1)^PIECETYPE(WhiteKing,KING)
The new position and the preferred position
g1
g1
The fluents of the init state
occupies(WhiteKing,e1)
BOARD(e1)
PIECETYPE(WhiteKing,KING)
REACHABLE(WhiteKing,f1)
BOARD(f1)
CASTLE(WhiteKing,g1)
BOARD(g1)
REACHABLE(WhiteKing,e2)
BOARD(e2)
CASTLE(WhiteKing,g1)
BOARD(g1)
REACHABLE(WhiteKing,d2)
BOARD(d2)
CASTLE(WhiteKing,g1)
BOARD(g1)
PROTECTEDBY(WhiteBishop2,f1)
PROTECTEDBY(WhiteBishop2,e2)
PROTECTEDBY(WhiteKnight1,e2)
PROTECTEDBY(WhiteKnight2,d2)
PROTECTEDBY(WhiteBishop1,d2)
PROTECTEDBY(WhiteRook2,f1)
PROTECTEDBY(WhiteQueen,d2)
PROTECTEDBY(WhiteQueen,e2)
PROTECTEDBY(WhiteKnight2,g1)
PROTECTEDBY(WhiteRook2,g1)
The fluents of the goal state
occupies(WhiteKing,g1)
PIECETYPE(WhiteKing,KING)
BOARD(g1)

Then from the Chess search algorithm, we get solved problem:
Returns with a plan: The fluents of end outcome:

occupies(WhiteKing,e1)
BOARD(e1)
PIECETYPE(WhiteKing,KING)
REACHABLE(WhiteKing,f1)
BOARD(f1)
CASTLE(WhiteKing,g1)
BOARD(g1)
REACHABLE(WhiteKing,e2)
BOARD(e2)
CASTLE(WhiteKing,g1)
BOARD(g1)
REACHABLE(WhiteKing,d2)
BOARD(d2)
CASTLE(WhiteKing,g1)
BOARD(g1)
PROTECTEDBY(WhiteBishop2,f1)
PROTECTEDBY(WhiteBishop2,e2)
PROTECTEDBY(WhiteKnight1,e2)
PROTECTEDBY(WhiteKnight2,d2)
PROTECTEDBY(WhiteBishop1,d2)
PROTECTEDBY(WhiteRook2,f1)
PROTECTEDBY(WhiteQueen,d2)
PROTECTEDBY(WhiteQueen,e2)
PROTECTEDBY(WhiteKnight2,g1)
PROTECTEDBY(WhiteRook2,g1)
OBS: NEW ENTRIES TO INITIAL STAGE:
occupies(WhiteKing,g1)
PIECETYPE(WhiteKing,KING)
occupies(WhiteKing,g1)
PIECETYPE(WhiteKing,KING)
The fluents of goal state:

occupies(WhiteKing,g1)
PIECETYPE(WhiteKing,KING)
BOARD(g1)