def prob(p):
p = float(p)
n = 1.0 - p
return {
'S': (('S', p), ('N', n)),
'N': (('N', p), ('S', n)),
'E': (('E', p), ('W', n)),
'W': (('W', p), ('E', n)),
}
STATES = ((0, 3), (0, 2), (1, 2), (0, 1), (1, 1), (0, 0))
if __name__ == '__main__':
print "\nInitial values:"
g = GridWorld(GRID, prob(1), STATES, 1, -4)
print g
i = g.value_iteration(0.1)
print "\nValues after %d iterations:" % i
print g
g = GridWorld(GRID, prob(0.8), STATES, 1, -4)
print "\nValue of (1,2) after first iteration: %.1f" % g.value(0, 3)
g = GridWorld(GRID, prob(0.8), STATES, 1, -4)
i = g.value_iteration(0.1)
print "\nValues after %d iterations:" % i
print g
from MDP.grid import GridWorld
GRID = [[0, 0, 0, 100],
[0, None, 0, -100],
[0, 0, 0, 0]]
PROB = {
'S':(('S', 0.8), ('W', 0.1), ('E', 0.1)),
'N':(('N', 0.8), ('E', 0.1), ('W', 0.1)),
'E':(('E', 0.8), ('S', 0.1), ('N', 0.1)),
'W':(('W', 0.8), ('N', 0.1), ('S', 0.1)),
}
STATES = ((0,2),(0,1),(1,2),(0,0),(2,2),(1,0),(2,1),(2,0),(2,3))
if __name__ == '__main__':
g = GridWorld(GRID, PROB, STATES, 1, -3)
v = g.value(0,2)
print "\nValue of (0,2) after first iteration: %.1f" % v
g.grid[0][2] = v
print "\nValue of (1,2) after first iteration: %.1f" % g.value(1,2)
print "\nInitial values:"
g = GridWorld(GRID, PROB, STATES, 1, -3)
print g
i = g.value_iteration(0.1)
print "\nValues after %d iterations:" % i
print g
