def sentence3():
"""Using the symbols WumpusAlive[1], WumpusAlive[0], WumpusBorn[0], and WumpusKilled[0],
created using the logic.PropSymbolExpr constructor, return a logic.PropSymbolExpr
instance that encodes the following English sentences (in this order):
The Wumpus is alive at time 1 if and only if the Wumpus was alive at time 0 and it was
not killed at time 0 or it was not alive and time 0 and it was born at time 0.
The Wumpus cannot both be alive at time 0 and be born at time 0.
The Wumpus is born at time 0.
"""
"*** YOUR CODE HERE ***"
#know the use of the PropSymbolExpr from logic.py
Alive_1 = logic.PropSymbolExpr("WumpusAlive", 1)
#print (Alive_1)
Alive_0 = logic.PropSymbolExpr("WumpusAlive", 0)
Born_0 = logic.PropSymbolExpr("WumpusBorn", 0)
Killed_0 = logic.PropSymbolExpr("WumpusKilled", 0)
One = Alive_1 % logic.disjoin(logic.conjoin(Alive_0, ~Killed_0),
logic.conjoin(~Alive_0, Born_0))
Two = ~logic.conjoin(Alive_0, Born_0)
Three = Born_0
return logic.conjoin(One, Two, Three)
util.raiseNotDefined()
def positionLogicPlan(problem):
"""
Given an instance of a PositionSearchProblem, return a list of actions that lead to the goal.
Available actions are game.Directions.{NORTH,SOUTH,EAST,WEST}
Note that STOP is not an available action.
"""
actions = [
game.Directions.EAST, game.Directions.SOUTH, game.Directions.WEST,
game.Directions.NORTH
]
init_t = util.manhattanDistance(problem.getStartState(),
problem.getGoalState())
goal_s = problem.getGoalState()
preds = getPredecessors(problem)
start_pos = problem.getStartState()
init_state = [logic.Expr("&", logic.PropSymbolExpr("P", start_pos[0],start_pos[1],0),\
*[logic.Expr("~", logic.PropSymbolExpr("P", s[0],s[1],0)) for s in preds.keys() if s != start_pos])]
for t in xrange(init_t, 51):
goal = [logic.PropSymbolExpr("P", goal_s[0], goal_s[1]), \
logic.to_cnf(logic.Expr(">>", logic.PropSymbolExpr("P", goal_s[0], goal_s[1]),\
logic.Expr("|", *[logic.PropSymbolExpr("P", goal_s[0], goal_s[1], time) for time in xrange(1,t+1)])))]
successors = generateSuccessorState(preds, t)
exps = goal + successors + init_state
model = logic.pycoSAT(exps)
if model:
return extractActionSequence(model, actions)
return []
def getFoodSentence(startState, action_delata, walls):
s = util.Queue()
visited = set()
startPosition, startFoodGrid = startState
StartExpr = logic.PropSymbolExpr(pacman_str, startPosition[0],
startPosition[1], 0)
s.push((startState, 0, StartExpr))
while not s.isEmpty():
curState, t, sentence = s.pop()
curPosition, curFoodGrid = curState
if (curFoodGrid.count() == 0):
return sentence
if curState in visited:
continue
visited.add(curState)
for action, v in action_delata.items():
nextPosition = (curPosition[0] + v[0], curPosition[1] + v[1])
nextFoodGrid = curFoodGrid.copy()
if nextFoodGrid[nextPosition[0]][nextPosition[1]]:
nextFoodGrid[nextPosition[0]][nextPosition[1]] = False
nextState = (nextPosition, nextFoodGrid)
Action_expr = logic.PropSymbolExpr(action, t)
Position_expr = logic.PropSymbolExpr(pacman_str, nextPosition[0],
nextPosition[1], t + 1)
nextSentence = logic.conjoin(
[sentence, Action_expr, Position_expr])
if not walls[nextPosition[0]][nextPosition[1]]:
s.push((nextState, t + 1, nextSentence))
def pacmanAliveSuccessorStateAxioms(x, y, t, num_ghosts):
"""
Successor state axiom for patrolling ghost state (x,y,t) (from t-1).
Current <==> (causes to stay) | (causes of current)
"""
ghost_strs = [
ghost_pos_str + str(ghost_num) for ghost_num in xrange(num_ghosts)
]
"*** YOUR CODE HERE ***"
no_ghost = []
for ghost in ghost_strs:
ghost_position_before = ~logic.PropSymbolExpr(ghost, x, y, t - 1)
no_ghost.append(ghost_position_before)
ghost_position_now = ~logic.PropSymbolExpr(ghost, x, y, t)
no_ghost.append(ghost_position_now)
no_ghost_here = logic.conjoin(no_ghost)
ghost_exists = ~(logic.conjoin(no_ghost))
pacman_alive_prev = logic.PropSymbolExpr(pacman_alive_str, t - 1)
pacman_not_there = ~logic.PropSymbolExpr(pacman_str, x, y, t)
return logic.PropSymbolExpr(pacman_alive_str, t) % (pacman_alive_prev & (
(no_ghost_here) | (ghost_exists & pacman_not_there)))
def ghostDirectionSuccessorStateAxioms(t, ghost_num, blocked_west_positions,
blocked_east_positions):
"""
Successor state axiom for patrolling ghost direction state (t) (from t-1).
west or east walls.
Current <==> (causes to stay) | (causes of current)
"""
pos_str = ghost_pos_str + str(ghost_num)
east_str = ghost_east_str + str(ghost_num)
"*** YOUR CODE HERE ***"
west_action = ~(logic.PropSymbolExpr(east_str, t - 1))
east_action = logic.PropSymbolExpr(east_str, t - 1)
west_list = []
east_list = []
for pos in blocked_east_positions:
x, y = pos
not_blocked_east = ~logic.PropSymbolExpr(pos_str, x, y, t)
lst = logic.conjoin(east_action, not_blocked_east)
east_list.append(lst)
for pos in blocked_west_positions:
x, y = pos
blocked_west = logic.PropSymbolExpr(pos_str, x, y, t)
lst = logic.conjoin(west_action, blocked_west)
west_list.append(lst)
east_list = logic.conjoin(east_list)
west_list = logic.disjoin(west_list)
return logic.PropSymbolExpr(east_str, t) % logic.disjoin(
east_list, west_list)
def ghostDirectionSuccessorStateAxioms(t, ghost_num, blocked_west_positions,
blocked_east_positions):
"""
Successor state axiom for patrolling ghost direction state (t) (from t-1).
west or east walls.
Current <==> (causes to stay) | (causes of current)
"""
pos_str = ghost_pos_str + str(ghost_num)
east_str = ghost_east_str + str(ghost_num)
move = logic.PropSymbolExpr(east_str, t - 1)
moveT = logic.PropSymbolExpr(east_str, t)
west_not_block = []
condition = []
for position in blocked_west_positions:
west_not_block += [
~logic.PropSymbolExpr(pos_str, position[0], position[1], t)
]
west_not_block = logic.conjoin(west_not_block)
east_not_block = []
for position in blocked_east_positions:
east_not_block += [
~logic.PropSymbolExpr(pos_str, position[0], position[1], t)
]
east_not_block = logic.conjoin(east_not_block)
if t == 0:
return east_not_block % moveT
return moveT % ((move & east_not_block) |
(~west_not_block & east_not_block) |
(~west_not_block & ~east_not_block & ~move))
def pacmanSuccessorStateAxioms(x, y, t, walls_grid):
"""
Successor state axiom for state (x,y,t) (from t-1), given the board (as a
grid representing the wall locations).
Current <==> (previous position at time t-1) & (took action to move to x, y)
"""
"*** YOUR CODE HERE ***"
def noWallHere(coord):
return not walls_grid[coord[0]][coord[1]]
listPrev = []
directions = ["East", "West", "South", "North"]
at = [(x - 1, y), (x + 1, y), (x, y + 1), (x, y - 1)]
for i in xrange(len(directions)):
direc = directions[i]
coord = at[i]
if noWallHere(coord):
prevAtHere = logic.PropSymbolExpr(pacman_str, coord[0], coord[1],
t - 1)
prevGoThere = logic.PropSymbolExpr(direc, t - 1)
listPrev.append(logic.conjoin(prevAtHere, prevGoThere))
pacmanNow = logic.PropSymbolExpr(pacman_str, x, y, t)
return pacmanNow % logic.disjoin(i for i in listPrev)
def sentence3():
"""Using the symbols WumpusAlive[1], WumpusAlive[0], WumpusBorn[0], and WumpusKilled[0],
created using the logic.PropSymbolExpr constructor, return a logic.PropSymbolExpr
instance that encodes the following English sentences (in this order):
The Wumpus is alive at time 1 if and only if the Wumpus was alive at time 0 and it was
not killed at time 0 or it was not alive and time 0 and it was born at time 0.
The Wumpus cannot both be alive at time 0 and be born at time 0.
The Wumpus is born at time 0.
"""
"*** YOUR CODE HERE ***"
WumpusAlive_1 = logic.PropSymbolExpr("WumpusAlive", 1)
WumpusAlive_0 = logic.PropSymbolExpr("WumpusAlive", 0)
WumpusBorn_0 = logic.PropSymbolExpr("WumpusBorn", 0)
WumpusKilled_0 = logic.PropSymbolExpr("WumpusKilled", 0)
clause_one = WumpusAlive_1 % ((WumpusAlive_0 & (~WumpusKilled_0)) | \
((~WumpusAlive_0) & WumpusBorn_0) )
clause_two = ~(WumpusAlive_0 & WumpusBorn_0)
clause_three = WumpusBorn_0
instance = logic.conjoin(clause_one, clause_two, clause_three)
return instance
def ghostDirectionSuccessorStateAxioms(t, ghost_num, blocked_west_positions,
blocked_east_positions):
"""
Successor state axiom for patrolling ghost direction state (t) (from t-1).
west or east walls.
Current <==> (causes to stay) | (causes of current)
"""
pos_str = ghost_pos_str + str(ghost_num)
east_str = ghost_east_str + str(ghost_num)
west_positions = list()
east_positions = list()
blocked_west_positions_copy = blocked_west_positions[:]
blocked_east_positions_copy = blocked_east_positions[:]
while blocked_west_positions_copy:
position = blocked_west_positions_copy.pop()
west_positions.append(
logic.PropSymbolExpr(pos_str, position[0], position[1], t))
while blocked_east_positions_copy:
position = blocked_east_positions_copy.pop()
east_positions.append(
logic.PropSymbolExpr(pos_str, position[0], position[1], t))
west_positions = logic.disjoin(west_positions)
east_positions = logic.disjoin(east_positions)
conditions = (west_positions & ~logic.PropSymbolExpr(east_str, t - 1)) | (
~east_positions & logic.PropSymbolExpr(east_str, t - 1))
final_axiom = logic.PropSymbolExpr(east_str, t) % conditions
return final_axiom
def get_ghost_axioms(locations, time):
axioms = []
for location in locations:
axioms.append(
~logic.PropSymbolExpr('P', location[0], location[1], time))
axioms.append(
~logic.PropSymbolExpr('P', location[0], location[1], time + 1))
return axioms
def positionLogicPlan(problem):
"""
Given an instance of a PositionPlanningProblem, return a list of actions that lead to the goal.
Available actions are game.Directions.{NORTH,SOUTH,EAST,WEST}
Note that STOP is not an available action.
"""
walls = problem.walls
width, height = problem.getWidth(), problem.getHeight()
MAX_TIME = 50
start_pos = problem.getStartState()
goal_pos = problem.getGoalState()
actions = ['North', 'South', 'East', 'West']
# pacman can only start at one position (with this and other constarin, there is no need to generate knowledge that pacman can not in two place at one time)
start_one_list = []
for x in range(1, width + 1):
for y in range(1, height + 1):
if (x, y) != start_pos:
start_one_list.append(
~logic.PropSymbolExpr(pacman_str, x, y, 0))
start_one = logic.conjoin(start_one_list)
#pacman start state
start_state = logic.PropSymbolExpr(pacman_str, start_pos[0], start_pos[1],
0)
#pacman is in start_pos and not in any other position
start = logic.conjoin(start_state, start_one)
one_action_list = []
transition_list = []
#update knowledge base through time
for t in range(1, MAX_TIME + 1):
goal = logic.PropSymbolExpr(pacman_str, goal_pos[0], goal_pos[1], t)
#can only take one action to get to current state
temp = []
for action in actions:
one = logic.PropSymbolExpr(action, t - 1)
temp.append(one)
step_one_action = exactlyOne(temp)
one_action_list.append(step_one_action)
for x in range(1, width + 1):
for y in range(1, height + 1):
if not walls[x][y]:
transition_list.append(
pacmanSuccessorStateAxioms(x, y, t, walls))
one_action = logic.conjoin(one_action_list)
one_action_list = [one_action]
transition = logic.conjoin(transition_list)
transition_list = [transition]
result = findModel(logic.conjoin(start, one_action, transition, goal))
if result is not False:
return extractActionSequence(result, actions)
def foodLogicPlan(problem):
"""
Given an instance of a FoodPlanningProblem, return a list of actions that help Pacman
eat all of the food.
Available actions are ['North', 'East', 'South', 'West']
Note that STOP is not an available action.
P[X,Y,Z,t] Z:food number
"""
walls = problem.walls
w, h = problem.getWidth(), problem.getHeight()
(x0, y0), food = problem.start
foodList = food.asList()
print("foodList", foodList)
cond = None
for max in range(1, 50):
if (len(foodList) == 0):
return []
lg = logic.PropSymbolExpr(pacman_str, x0, y0, 50 - max)
if cond == None:
cond = logic.to_cnf(precond(problem, max))
lg = lg & cond
else:
cond = cond & logic.to_cnf(precond(problem, max))
lg = logic.conjoin([lg, cond])
#print(lg)
print(max)
for t in range(50 - max + 1, 51):
for x in range(1, w + 1):
for y in range(1, h + 1):
if (not walls[x][y]):
axiom = pacmanSuccessorStateAxioms(x, y, t, walls)
lg = lg & logic.to_cnf(axiom)
#print(lg)
for f in foodList:
tmp = []
for t in range(50 - max, 50):
tmp.append(logic.PropSymbolExpr(pacman_str, f[0], f[1], t))
if len(tmp) != 0:
lg = lg & atLeastOne(tmp)
res = findModel(lg)
#print("res: ", res, "\n")
if res != False:
print(
"actions:",
extractActionSequence(res, ['North', 'East', 'South', 'West']))
return extractActionSequence(res,
['North', 'East', 'South', 'West'])
def pacmanSuccessorStateAxioms(x, y, t, walls_grid):
"""
Successor state axiom for state (x,y,t) (from t-1), given the board (as a
grid representing the wall locations).
Current <==> (previous position at time t-1) & (took action to move to x, y)
"""
"*** YOUR CODE HERE ***"
current_pos = logic.PropSymbolExpr(pacman_str, x, y, t)
pre = []
if not walls_grid[x][y - 1]:
pre_pos = logic.PropSymbolExpr(pacman_str, x, y - 1, t - 1)
move = logic.PropSymbolExpr("North", t - 1)
pre.append(move & pre_pos)
if not walls_grid[x][y + 1]:
pre_pos = logic.PropSymbolExpr(pacman_str, x, y + 1, t - 1)
move = logic.PropSymbolExpr("South", t - 1)
pre.append(move & pre_pos)
if not walls_grid[x - 1][y]:
pre_pos = logic.PropSymbolExpr(pacman_str, x - 1, y, t - 1)
move = logic.PropSymbolExpr("East", t - 1)
pre.append(move & pre_pos)
if not walls_grid[x + 1][y]:
pre_pos = logic.PropSymbolExpr(pacman_str, x + 1, y, t - 1)
move = logic.PropSymbolExpr("West", t - 1)
pre.append(move & pre_pos)
all_pre = logic.disjoin(pre)
return current_pos % all_pre
def pacmanSuccessorStateAxioms(x, y, t, walls_grid):
"""
Successor state axiom for state (x,y,t) (from t-1), given the board (as a
grid representing the wall locations).
Current <==> (previous position at time t-1) & (took action to move to x, y)
"""
moves = []
if not walls_grid[x + 1][y]:
moves.append(
logic.PropSymbolExpr(pacman_str, x + 1, y, t - 1)
& logic.PropSymbolExpr('West', t - 1))
if not walls_grid[x - 1][y]:
moves.append(
logic.PropSymbolExpr(pacman_str, x - 1, y, t - 1)
& logic.PropSymbolExpr('East', t - 1))
if not walls_grid[x][y + 1]:
moves.append(
logic.PropSymbolExpr(pacman_str, x, y + 1, t - 1)
& logic.PropSymbolExpr('South', t - 1))
if not walls_grid[x][y - 1]:
moves.append(
logic.PropSymbolExpr(pacman_str, x, y - 1, t - 1)
& logic.PropSymbolExpr('North', t - 1))
return logic.PropSymbolExpr(pacman_str, x, y, t) % (logic.disjoin(moves))
def isSafe(position, pkeReadings, knownSafePositions, walls):
exprList = []
ghostStr = "G"
pkeStr = "PKE"
positionSymbol = logic.PropSymbolExpr(ghostStr,position[0],position[1])
for (x,y) in knownSafePositions:
exprList += [~logic.PropSymbolExpr(ghostStr,x,y)]
for ((x,y), pkeReading) in pkeReadings.items():
pkeSymbol = logic.PropSymbolExpr(pkeStr,x,y)
if pkeReading:
exprList += [pkeSymbol]
else:
exprList += [~pkeSymbol]
allNeighbors = [(x-1,y), (x+1,y), (x,y-1), (x,y+1)]
neighborSymbols = []
for (nx,ny) in allNeighbors:
if not walls[nx][ny]:
neighborSymbols += [logic.PropSymbolExpr(ghostStr,nx,ny)]
pkeExpr = pkeSymbol % reduce((lambda a,b: a|b), neighborSymbols)
exprList += [logic.to_cnf(pkeExpr)]
# # A pke reading in any square means that there is a ghost in at least one adjacent square
# for x in xrange(1,walls.width-1):
# for y in xrange(1,walls.height-1):
# if walls[x][y]:
# continue
#
# allNeighbors = [(x-1,y), (x+1,y), (x,y-1), (x,y+1)]
# neighborSymbols = []
# for (nx,ny) in allNeighbors:
# if not walls[nx][ny]:
# neighborSymbols += [logic.PropSymbolExpr(ghostStr,nx,ny)]
#
# pkeSymbol = logic.PropSymbolExpr(pkeStr,x,y)
# pkeExpr = pkeSymbol % reduce((lambda a,b: a|b), neighborSymbols)
# exprList += [logic.to_cnf(pkeExpr)]
ghostModel = logic.pycoSAT(exprList + [positionSymbol])
# print "ghostModel={}".format(ghostModel)
if not ghostModel:
# print "exprList={}".format(exprList + [positionSymbol])
return True;
else:
noGhostModel = logic.pycoSAT(exprList + [~positionSymbol])
# print "noGhostModel={}".format(noGhostModel)
if not noGhostModel:
return False;
else:
return None
def pacmanSuccessorStateAxioms(x, y, t, walls_grid):
"""
Successor state axiom for state (x,y,t) (from t-1), given the board (as a
grid representing the wall locations).
Current <==> (previous position at time t-1) & (took action to move to x, y)
"""
"*** YOUR CODE HERE ***"
expr = []
if (not walls_grid[x][y - 1]):
expr += [
logic.PropSymbolExpr(pacman_str, x, y - 1, t - 1)
& logic.PropSymbolExpr('North', t - 1)
]
if (not walls_grid[x][y + 1]):
expr += [
logic.PropSymbolExpr(pacman_str, x, y + 1, t - 1)
& logic.PropSymbolExpr('South', t - 1)
]
if (not walls_grid[x - 1][y]):
expr += [
logic.PropSymbolExpr(pacman_str, x - 1, y, t - 1)
& logic.PropSymbolExpr('East', t - 1)
]
if (not walls_grid[x + 1][y]):
expr += [
logic.PropSymbolExpr(pacman_str, x + 1, y, t - 1)
& logic.PropSymbolExpr('West', t - 1)
]
return logic.PropSymbolExpr(pacman_str, x, y, t) % logic.disjoin(
expr) # Replace this with your expression
def pacmanSuccessorStateAxioms(x, y, t, walls_grid):
"""
Successor state axiom for state (x,y,t) (from t-1), given the board (as a
grid representing the wall locations).
Current <==> (previous position at time t-1) & (took action to move to x, y)
"""
"*** YOUR CODE HERE ***"
# init current/final position
current = logic.PropSymbolExpr(pacman_str, x, y, t)
test = []
if walls_grid[x+1][y] != True:
action = logic.PropSymbolExpr(pacman_str, x+1, y, t-1) & logic.PropSymbolExpr('West', t-1)
test.append(action)
successor_nodes.append((x+1, y, t))
if walls_grid[x-1][y] != True:
action2 = logic.PropSymbolExpr(pacman_str, x-1, y, t-1) & logic.PropSymbolExpr('East', t-1)
test.append(action2)
successor_nodes.append((x+1, y, t))
if walls_grid[x][y+1] != True:
action3 = logic.PropSymbolExpr(pacman_str, x, y+1, t-1) & logic.PropSymbolExpr('South', t-1)
test.append(action3)
successor_nodes.append((x+1, y, t))
if walls_grid[x][y-1] != True:
action4 = logic.PropSymbolExpr(pacman_str, x, y-1, t-1) & logic.PropSymbolExpr('North', t-1)
test.append(action4)
successor_nodes.append((x+1, y, t))
return current % logic.disjoin(test)
def pacmanSuccessorStateAxioms(x, y, t, walls_grid):
"""
Successor state axiom for state (x,y,t) (from t-1), given the board (as a
grid representing the wall locations).
Current <==> (previous position at time t-1) & (took action to move to x, y)
"""
"*** YOUR CODE HERE ***"
successor_list = []
if 0 <= x - 1 < walls_grid.width and 0 <= y < walls_grid.height:
if not walls_grid.data[x - 1][y]:
location = logic.PropSymbolExpr('P', x - 1, y, t - 1)
action = logic.PropSymbolExpr('East', t - 1)
successor_list.append(location & action)
if 0 <= x + 1 < walls_grid.width and 0 <= y < walls_grid.height:
if not walls_grid.data[x + 1][y]:
location = logic.PropSymbolExpr('P', x + 1, y, t - 1)
action = logic.PropSymbolExpr('West', t - 1)
successor_list.append(location & action)
if 0 <= x < walls_grid.width and 0 <= y - 1 < walls_grid.height:
if not walls_grid.data[x][y - 1]:
location = logic.PropSymbolExpr('P', x, y - 1, t - 1)
action = logic.PropSymbolExpr('North', t - 1)
successor_list.append(location & action)
if 0 <= x < walls_grid.width and 0 <= y + 1 < walls_grid.height:
if not walls_grid.data[x][y + 1]:
location = logic.PropSymbolExpr('P', x, y + 1, t - 1)
action = logic.PropSymbolExpr('South', t - 1)
successor_list.append(location & action)
return logic.PropSymbolExpr('P', x, y, t) % logic.associate(
'|', successor_list)
def positionLogicPlan(problem):
"""
Given an instance of a PositionPlanningProblem, return a list of actions that lead to the goal.
Available actions are game.Directions.{NORTH,SOUTH,EAST,WEST}
Note that STOP is not an available action.
"""
walls = problem.walls
width, height = problem.getWidth(), problem.getHeight()
available_action = ['North', 'East', 'South', 'West'] # evacuate STOP
"*** YOUR CODE HERE ***"
# get start/goal loaction
start = problem.getStartState()
goal = problem.getGoalState()
start_state = logic.PropSymbolExpr("P", start[0], start[1], 0)
start_logic = []
for i in range(1, width+1):
for j in range(1, height+1):
start_logic.append(logic.PropSymbolExpr("P", i, j, 0))
start_logic = exactlyOne(start_logic)
start_logic = logic.conjoin(start_logic, start_state)
# note that we must assert any other position is not allowed, otherwise it will cause weird error
t = 1 # initial time
# note that time start from 1 but not 0
path = False
while not path:
# goal state
goal_state = logic.PropSymbolExpr("P", goal[0], goal[1], t+1)
# build succession logic
successor = []
for k in range(1, t+2): # note here must be t+2
for i in range(1, width + 1): # skip the most-outside wall
for j in range(1, height + 1):
if not walls[i][j]: # if (x, y) is not a wall
successor.append(pacmanSuccessorStateAxioms(i, j, k, walls))
successor = logic.conjoin(successor)
action_taken = []
for i in range(0, t + 1):# last one is t
all_action = []
for action in available_action:
all_action += [logic.PropSymbolExpr(action, i)]
# one step must take exactly one action
action_taken.append(exactlyOne(all_action))
# each step must take action
each_step_action = logic.conjoin(action_taken)
# assemble model
model = logic.conjoin(start_logic, goal_state, each_step_action, successor)
path = findModel(model)
# complicated init state & goal state & way to achieve goal & all possible action can be taken & all possible successors to any point
t += 1
return extractActionSequence(path, available_action)
def food_goal_sentence(problem, time):
goal = []
food_list = problem.getStartState()[1].asList()
for food in food_list:
goal.append(~logic.PropSymbolExpr("F", food[0], food[1]))
expressions = []
for position in food_list:
expressions.append(
logic.PropSymbolExpr("P", position[0], position[1], time))
goal.append(atLeastOne(expressions))
return goal
def generate_initial_statements(problem):
temp_list = []
initial_position_expr = logic.PropSymbolExpr("P", start[0], start[1], time)
for x in range(0, problem.getWidth()):
for y in range(0, problem.getHeight()):
if (x,y) == (start[0], start[1]):
continue
else:
temp_list.append(logic.PropSymbolExpr("P", x, y, time))
initial_position_expr = initial_position_expr & ~(logic.associate('|', temp_list))
return initial_position_expr
def positionLogicPlan(problem):
"""
Given an instance of a PositionPlanningProblem, return a list of actions that lead to the goal.
Available actions are game.Directions.{NORTH,SOUTH,EAST,WEST}
Note that STOP is not an available action.
"""
walls = problem.walls
width, height = problem.getWidth(), problem.getHeight()
start = problem.getStartState()
end = problem.getGoalState()
actions = ['North', 'South', 'East', 'West']
not_walls = [(x, y)
for x, y in product(range(1, width + 1), range(1, height + 1))
if not walls[x][y]]
# init^0
init = logic.PropSymbolExpr(pacman_str, start[0], start[1], 0)
for i in range(1, width + 1):
for j in range(1, height + 1):
if (i, j) != start:
init = logic.conjoin(
init, (~logic.PropSymbolExpr(pacman_str, i, j, 0)))
t = 1
assertion = lambda t: logic.PropSymbolExpr(pacman_str, end[0], end[1], t)
transition = lambda t: logic.conjoin(
[pacmanSuccessorStateAxioms(x, y, t, walls) for x, y in not_walls])
constraint_action = lambda t: exactlyOne(
[logic.PropSymbolExpr(action, t - 1) for action in actions])
constraint_position = lambda t: exactlyOne(
[logic.PropSymbolExpr(pacman_str, x, y, t - 1) for x, y in not_walls])
transition_all = transition(1)
constraint_action_all = constraint_action(1)
constraint_position_all = constraint_position(1)
while True:
if t != 1:
transition_all = logic.conjoin(transition_all, transition(t))
constraint_action_all = logic.conjoin(constraint_action_all,
constraint_action(t))
constraint_position_all = logic.conjoin(constraint_position_all,
constraint_position(t))
model = findModel(
logic.conjoin(init, transition_all, assertion(t),
constraint_action_all, constraint_position_all))
# print(model)
if model is not False:
# print(extractActionSequence(model, actions))
return extractActionSequence(model, actions)
else:
t += 1
def possActs(x, y, t, walls_grid, problem):
ls = [(-1, 0), (1, 0), (0, -1), (0, 1)]
dir = ["East", "West", "North", "South"]
acts = []
for i in range(4):
(mx, my) = ls[i]
#print("xfs, yf", (mx + x, my + y))
if (validIdx(mx + x, my + y, problem)
and not walls_grid[mx + x][my + y]):
at = logic.PropSymbolExpr(pacman_str, mx + x, my + y, t - 1)
mv = logic.PropSymbolExpr(dir[i], t - 1)
acts.append((at & mv))
return acts
def get_food_axioms(problem, max_time):
models = []
food_list = problem.getStartState()[1].asList()
for food in food_list:
expressions = []
for t in xrange(max_time + 1):
expressions.append(logic.PropSymbolExpr("P", food[0], food[1], t))
if expressions:
position_sentences = atLeastOne(expressions)
before_cnf = ~logic.PropSymbolExpr("F", food[0],
food[1]) % position_sentences
models.append(logic.to_cnf(before_cnf))
return models
def foodLogicPlan(problem):
"""
Given an instance of a FoodSearchProblem, return a list of actions that help Pacman
eat all of the food.
Available actions are game.Directions.{NORTH,SOUTH,EAST,WEST}
Note that STOP is not an available action.
"""
# need a list where all the food is
# go through with the logic phrase, for each food make sure at some time step t I will be there
actions = [
game.Directions.EAST, game.Directions.SOUTH, game.Directions.WEST,
game.Directions.NORTH
]
# this is my food grid as a list [(x,y), (x,y) ...]
food_list = problem.getStartState()[1].asList()
# this is a list of the distances from my start state to each food on the grid
manhattan_food_distances = [
util.manhattanDistance(problem.getStartState()[0], food)
for food in food_list
]
# for the predecessors function
extractState = lambda x: x[0][0]
generateState = lambda x: (x, problem.getStartState()[1])
# return the food that is furthest away
init_t = max(manhattan_food_distances)
preds = getPredecessors(problem, extractState, generateState)
start_pos = problem.getStartState()[0]
init_state = [logic.Expr("&", logic.PropSymbolExpr("P", start_pos[0],start_pos[1],0),\
*[logic.Expr("~", logic.PropSymbolExpr("P", s[0],s[1],0)) for s in preds.keys() if s != start_pos])]
for t in xrange(init_t, 51):
goal_list = []
for food in food_list: # food is an (x, y) coordinate
goal_list.append([logic.PropSymbolExpr("P", food[0], food[1]), \
logic.to_cnf(logic.Expr(">>", logic.PropSymbolExpr("P", food[0], food[1]),\
logic.Expr("|", *[logic.PropSymbolExpr("P", food[0], food[1], time) for time in xrange(1,t+1)])))])
successors = generateSuccessorState(preds, t)
# makes goal_list a list, previously was a list of lists
goal_list = reduce(lambda x, y: x + y, goal_list)
exps = goal_list + successors + init_state
model = logic.pycoSAT(exps)
if model:
return extractActionSequence(model, actions)
return []
def transition_models(problem, time, actions, legal_actions):
"""
Most important function, writes axioms about our fluents
"""
models = []
for i in xrange(1, problem.getWidth() + 1):
for j in xrange(1, problem.getHeight() + 1):
if not problem.isWall((i, j)):
current_symbol = logic.PropSymbolExpr('P', i, j, time)
expressions = []
for action in actions:
previous_symbol = None
action_symbol = None
if action == Directions.EAST:
if (i - 1, j, action) in legal_actions:
previous_symbol = logic.PropSymbolExpr(
'P', i - 1, j, time - 1)
action_symbol = logic.PropSymbolExpr(
action, time - 1)
else:
continue
elif action == Directions.WEST:
if (i + 1, j, action) in legal_actions:
previous_symbol = logic.PropSymbolExpr(
'P', i + 1, j, time - 1)
action_symbol = logic.PropSymbolExpr(
action, time - 1)
else:
continue
elif action == Directions.NORTH:
if (i, j - 1, action) in legal_actions:
previous_symbol = logic.PropSymbolExpr(
'P', i, j - 1, time - 1)
action_symbol = logic.PropSymbolExpr(
action, time - 1)
else:
continue
elif action == Directions.SOUTH:
if (i, j + 1, action) in legal_actions:
previous_symbol = logic.PropSymbolExpr(
'P', i, j + 1, time - 1)
action_symbol = logic.PropSymbolExpr(
action, time - 1)
else:
continue
# NOTE: SHOULD NOT NEED TO STOP!
# elif action == Directions.STOP:
# pass
expressions.append(previous_symbol & action_symbol)
# before_cnf = current_symbol % atLeastOne(expressions)
models.append(
logic.to_cnf(
current_symbol %
atLeastOne(expressions))) # % means <=>, this is VERY UGLY
return models
def positionLogicPlan(problem):
"""
Given an instance of a PositionPlanningProblem, return a list of actions that lead to the goal.
Available actions are game.Directions.{NORTH,SOUTH,EAST,WEST}
Note that STOP is not an available action.
"""
walls = problem.walls
width, height = problem.getWidth(), problem.getHeight()
"*** YOUR CODE HERE ***"
actions = ['North', 'South', 'East', 'West']
startState = []
initialX, initialY = problem.getStartState()
initial = logic.PropSymbolExpr(pacman_str, initialX, initialY, 0)
goalX, goalY = problem.getGoalState()
goalSuccessors = []
goalActions = []
steps = 50
for x in range(1, width + 1):
for y in range(1, height + 1):
if not (x, y) in walls.asList():
startState.append(logic.PropSymbolExpr(pacman_str, x, y, 0))
for i in range(1, steps):
successors = []
start = exactlyOne(startState) # needed for goal
goal = logic.PropSymbolExpr(pacman_str, goalX, goalY, i)
for x in range(1, width + 1):
for y in range(1, height + 1):
if (x, y) not in walls.asList():
successors.append(
pacmanSuccessorStateAxioms(x, y, i, walls))
successor = logic.conjoin(successors)
action = []
for a in actions:
action.append(logic.PropSymbolExpr(a, i - 1))
goalActions.append(exactlyOne(action))
goalSuccessors.append(successor)
# print("start: ", start)
# print("initial: ", initial)
# print("goal: ", goal)
# print("goalActions: ", goalActions)
# print("goalSuccessors: ", goalSuccessors)
isGoal = findModel(
logic.conjoin([
start, initial, goal,
logic.conjoin(goalSuccessors),
logic.conjoin(goalActions)
]))
if isGoal:
return extractActionSequence(isGoal, actions)
def pacmanSuccessorStateAxioms(x, y, t, walls_grid):
"""
Successor state axiom for state (x,y,t) (from t-1), given the board (as a
grid representing the wall locations).
Current <==> (previous position at time t-1) & (took action to move to x, y)
"""
"*** YOUR CODE HERE ***"
P_x_y_t = logic.PropSymbolExpr(pacman_str, x, y, t)
neighbor = [(i, j) for i, j in zip([(x, y - 1), (x, y + 1), (
x - 1, y), (x + 1, y)], ['North', 'South', 'East', 'West'])
if not walls_grid[i[0]][i[1]]]
return P_x_y_t % logic.disjoin(
[(logic.PropSymbolExpr(pacman_str, i[0][0], i[0][1], t - 1)
& logic.PropSymbolExpr(i[1], t - 1)) for i in neighbor])
def extractActionSequence(model, actions):
"""
Convert a model in to an ordered list of actions.
model: Propositional logic model stored as a dictionary with keys being
the symbol strings and values being Boolean: True or False
Example:
>>> model = {"North[3]":True, "P[3,4,1]":True, "P[3,3,1]":False, "West[1]":True, "GhostScary":True, "West[3]":False, "South[2]":True, "East[1]":False}
>>> actions = ['North', 'South', 'East', 'West']
>>> plan = extractActionSequence(model, actions)
>>> print plan
['West', 'South', 'North']
"""
"*** YOUR CODE HERE ***"
if not model:
return []
ret = []
i = 0
while True:
flag = False
for action in actions:
symbol = logic.PropSymbolExpr(action, i)
if symbol in model and model[symbol]:
ret += [action]
flag = True
if not flag:
break
i += 1
print ret
return ret
def extractActionSequence(model, actions):
"""
Convert a model in to an ordered list of actions.
model: Propositional logic model stored as a dictionary with keys being
the symbol strings and values being Boolean: True or False
Example:
>>> model = {"North[3]":True, "P[3,4,1]":True, "P[3,3,1]":False, "West[1]":True, "GhostScary":True, "West[3]":False, "South[2]":True, "East[1]":False}
>>> actions = ['North', 'South', 'East', 'West']
>>> plan = extractActionSequence(model, actions)
>>> print plan
['West', 'South', 'North']
"""
"*** YOUR CODE HERE ***"
plan = []
my_actions = []
for i in model:
my_string = str(i)
tmp1 = my_string.index('[')
tmp2 = my_string.index(']')
if my_string[:tmp1] in actions:
expr = logic.PropSymbolExpr(my_string[:tmp1],
int(my_string[tmp1 + 1:tmp2]))
if model[expr] == True:
my_actions.append(
(my_string[:tmp1], int(my_string[tmp1 + 1:tmp2])))
for i in range(len(my_actions)):
for j in range(len(my_actions)):
if my_actions[j][1] == i:
plan.append(my_actions[j][0])
return plan