def test_tiger():
S = ['left', 'right']
A = ['left', 'right', 'listen']
O = ['left', 'right']
discount = 0.95
def T(s, a, sp):
if a == 'listen':
return s == sp
else: # a door is opened
return 0.5 #reset
def Z(a, sp, o):
if a == 'listen':
if o == sp:
return 0.85
else:
return 0.15
else:
return 0.5
def R(s, a):
if a == 'listen':
return -1.0
elif s == a: # the tiger was found
return -100.0
else: # the tiger was escaped
return 10.0
m = DiscreteExplicitPOMDP(S, A, O, T, Z, R, discount)
solver = QMDPSolver()
policy = solve(solver, m)
print('alpha vectors:')
for v in alphavectors(policy):
print(v)
print()
rsum = 0.0
for step in stepthrough(m, policy, max_steps=10):
print('s:', step.s)
print('b:', [pdf(step.b, x) for x in S])
print('a:', step.a)
print('o:', step.o, '\n')
rsum += step.r
print('Undiscounted reward was', rsum)
def test_lightdark():
r = 60
light_loc = 10
def transition(s, a):
if a == 0:
return Deterministic(r + 1)
else:
return Deterministic(min(max(s + a, -r), r))
def observation(s, a, sp):
return Normal(sp, abs(sp - light_loc) + 0.0001)
def reward(s, a, sp):
if a == 0:
return 100.0 if s == 0 else -100.0
else:
return -1.0
m = QuickPOMDP(states=range(-r, r + 2),
actions=[-10, -1, 0, 1, 10],
discount=0.95,
isterminal=lambda s: s < -r or s > r,
obstype=Float64,
transition=transition,
observation=observation,
reward=reward,
initialstate=Uniform(range(-r // 2, r // 2 + 1)))
solver = QMDPSolver()
policy = solve(solver, m)
print('alpha vectors:')
for v in alphavectors(policy):
print(v)
print()
rsum = 0.0
for step in stepthrough(m, policy, max_steps=10):
print('s:', step.s)
print('a:', step.a)
print('o:', step.o, '\n')
rsum += step.r
print('Undiscounted reward was', rsum)
return 0.15
else:
return 0.5
def R(s, a):
if a == 'listen':
return -1.0
elif s == a: # the tiger was found
return -100.0
else: # the tiger was escaped
return 10.0
m = follow.GenerativePOMDP(S, A, O, T, Z, R, γ)
solver = POMCPOWSolver()
policy = solve(solver, m)
print()
rsum = 0.0
for step in stepthrough(m, policy, max_steps=10):
print('s:', step.s)
print('a:', step.a)
print('r:', step.r, '\n')
print('sp:', step.sp, '\n')
rsum += step.r
print('Undiscounted reward was', rsum)