si23traktor/graph_search.py

75 lines
2.8 KiB
Python

class Node:
def __init__(self, state, parent='', action=''):
self.state = state
self.parent = parent
self.action = action
class Search:
def __init__(self, cell_size, cell_number):
self.cell_size = cell_size
self.cell_number = cell_number
def succ(self, state):
x = state[0]
y = state[1]
angle = state[2]
angles = {0: 'UP', 90: 'RIGHT', 270: 'LEFT', 180: 'DOWN'}
match(angles[angle]):
case 'UP':
possible = [['left', x, y, 270], ['right', x, y, 90]]
if y != 0: possible.append(['move', x, y - self.cell_size, 0])
return possible
case 'RIGHT':
possible = [['left', x, y, 0], ['right', x, y, 180]]
if x != self.cell_size*(self.cell_number-1): possible.append(['move', x + self.cell_size, y, 90])
return possible
case 'DOWN':
possible = [['left', x, y, 90], ['right', x, y, 270]]
if y != self.cell_size*(self.cell_number-1): possible.append(['move', x, y + self.cell_size, 180])
return possible
case 'LEFT':
possible = [['left', x, y, 180], ['right', x, y, 0]]
if x != 0: possible.append(['move', x - self.cell_size, y, 270])
return possible
def graphsearch(self, istate, goaltest):
x = istate[0]
y = istate[1]
angle = istate[2]
fringe = [Node([x, y, angle])] # queue (moves/states to check)
fringe_state = [fringe[0].state]
explored = []
while True:
if len(fringe) == 0:
return False
elem = fringe.pop(0)
fringe_state.pop(0)
# if goal_test(elem.state):
# return
# print(elem.state[0], elem.state[1], elem.state[2])
if elem.state[0] == goaltest[0] and elem.state[1] == goaltest[1]: # checks if we reached the given point
steps = []
while elem.parent != '':
steps.append([elem.action, elem.state[0], elem.state[1]]) # should return only elem.action in prod
elem = elem.parent
steps.reverse()
print(steps) # only for dev
return steps
explored.append(elem.state)
for (action, state_x, state_y, state_angle) in self.succ(elem.state):
if [state_x, state_y, state_angle] not in fringe_state and \
[state_x, state_y, state_angle] not in explored:
x = Node([state_x, state_y, state_angle])
x.parent = elem
x.action = action
fringe.append(x)
fringe_state.append(x.state)