Exemple #1
0
    def search(self, vobj):
        frontier = PriorityQueue()
        frontier.put(self.start, 0)
        came_from = {}
        cost_so_far = {}
        came_from[self.start] = None
        cost_so_far[self.start] = 0

        while not frontier.empty():
            current = frontier.get()

            if current == self.goal:
                break

            for next in self.graph.neighbors(current):
                new_cost = cost_so_far[current] + self.graph.cost(
                    current, next)

                if next not in cost_so_far or new_cost < cost_so_far[next]:
                    cost_so_far[next] = new_cost
                    priority = new_cost + self.heuristic(self.goal, next)
                    frontier.put(next, priority)
                    came_from[next] = current

        # Reconstruct path
        path = [current]
        while current != self.start:
            current = came_from[current]
            path.append(current)

        nppath = np.asarray(path[::-4]) * self.graph.gridsize
        return np.copy(nppath[:])
Exemple #2
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def travel(dist_mat, startcity=0):
    optimal_tour = []
    u = Node()
    pq = PriorityQueue()
    opt_len = 0
    v = Node(level=0, path=[0])
    min_len = sys.maxsize
    v.bound = bound(dist_mat, v)
    pq.put(v)
    while not pq.empty():
        v = pq.get()
        if v.bound < min_len:
            u.level = v.level + 1
            for i in filter(lambda x: x not in v.path, range(1, num_cities)):
                u.path = v.path[:]
                u.path.append(i)
                if u.level == num_cities - 2:
                    l = set(range(1, num_cities)) - set(u.path)
                    u.path.append(list(l)[0])
                    u.path.append(0)

                    _len = length(dist_mat, u)
                    if _len < min_len:
                        min_len = _len
                        opt_len = _len
                        optimal_tour = u.path[:]
                else:
                    u.bound = bound(dist_mat, u)
                    if u.bound < min_len:
                        pq.put(u)
                # make a new node at each iteration!
                u = Node(level=u.level)

    return optimal_tour, opt_len
    def search(self, vobj):
        frontier = PriorityQueue()
        frontier.put(self.start, 0)
        came_from = {}
        cost_so_far = {}
        came_from[self.start] = None
        cost_so_far[self.start] = 0

        while not frontier.empty():
            current = frontier.get()

            if current == self.goal:
                break

            for next in self.graph.neighbors(current):
                new_cost = cost_so_far[current] + self.graph.cost(current, next)

                if next not in cost_so_far or new_cost < cost_so_far[next]:
                    cost_so_far[next] = new_cost
                    priority = new_cost + self.heuristic(self.goal, next)
                    frontier.put(next, priority)
                    came_from[next] = current

        # Reconstruct path
        path = [current]
        while current != self.start:
            current = came_from[current]
            path.append(current)

        nppath = np.asarray(path[::-4]) * self.graph.gridsize
        return np.copy(nppath[:])
Exemple #4
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    def a_star_search(self, h_type='zero', visualize=False):
        frontier = PriorityQueue()  # The OPENLIST
        frontier.put(self.start, 0)  # PUT START IN THE OPENLIST
        parent = {}  # parent, {loc: parent}
        # g function dict, {loc: f(loc)}, CLOSED LIST BASICALLY
        g = {}
        parent[self.start] = None
        g[self.start] = 0
        self.h_type = h_type
        if visualize:
            fig = plt.figure()
            ax = fig.add_subplot(1, 1, 1)
            ax.set_xlim(-100, 100)
            ax.set_ylim(-100, 100)
        while not frontier.empty():
            current = frontier.get(
            )  # update current to be the item with best priority

            if visualize:
                ax.plot(current[0], current[1], "xc")

            # early exit if we reached our goal
            if current == self.goal:
                break
            for next in self.graph.neighbors(current):
                g_next = g[current] + self.graph.cost(current, next)
                # if next location not in CLOSED LIST or its cost is less than before
                # Newer implementation
                if next not in g or g_next < g[next]:
                    g[next] = g_next
                    if self.h_type == 'zero':
                        priority = g_next
                    else:
                        priority = g_next + self.heuristic(
                            self.goal, next, self.h_type)
                    frontier.put(next, priority)
                    parent[next] = current

        if visualize:
            ax.plot(parent[0], parent[1], "-r")
            fig.show()

        self.parent = parent
        self.g = g
        return parent, g
Exemple #5
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    def search_path(self, start, goal, heuristic, is_walkable):
        frontier = PriorityQueue()
        frontier.put(start, 0)
        came_from = {}
        came_from[start] = None

        while not frontier.empty():
            current = frontier.get()

            if current == goal:
                break

            for next in self.neighbors(current, is_walkable):
                if next not in came_from:
                    priority = heuristic(goal, next)
                    frontier.put(next, priority)
                    came_from[next] = current

        if current != goal:
            return False

        return self.reconstruct_path(came_from, start, goal)
Exemple #6
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class Simulator(SimulatorBase):
    EVENT_QUEUE_THRESHOLD = 100

    def __init__(self):
        self.modules = {}
        self.module_type_map = defaultdict(deque)

        self.device_state = DeviceState()
        self.event_queue = PriorityQueue()
        self.alarms = []
        self.modules = {}
        self.event_listeners = defaultdict(deque)
        self.trace_reader = None
        self.verbose = False
        self.debug_mode = False
        self.debug_interval = 1
        self.debug_interval_cnt = 0

    def has_module_instance(self, name):
        return name in self.modules

    def get_module_instance(self, name):
        return self.modules[name]

    def get_module_for_type(self, module_type):
        if module_type in self.module_type_map:
            return self.module_type_map[module_type.value][0]
        else:
            return None

    def register(self, sim_module, override=False):
        if not isinstance(sim_module, SimModule):
            raise TypeError("Expected SimModule object")

        if sim_module.get_name() in self.modules:
            raise Exception("Module %s already exists" % sim_module.get_name())

        self.modules[sim_module.get_name()] = sim_module

        if override:
            self.module_type_map[sim_module.get_type().value].appendleft(
                sim_module)
        else:
            self.module_type_map[sim_module.get_type().value].append(
                sim_module)

    def build(self, args):
        self.verbose = args.verbose
        self.debug_mode = args.debug

        # Instantiate necessary modules based on config files
        config = configparser.ConfigParser()
        config.read(args.sim_config)

        config['DEFAULT'] = {'modules': ''}

        if 'Simulator' not in config:
            raise Exception("Simulator section missing from config file")

        sim_settings = config['Simulator']
        modules_str = sim_settings['modules']
        modules_list = modules_str.split(' ')

        for module_name in modules_list:
            module_settings = {}
            if module_name in config:
                module_settings = config[module_name]

            self.register(
                get_simulator_module(module_name, self, module_settings))

        # Build list of modules
        for module in self.modules.values():
            module.build()

    def run(self, trace_file):
        self.trace_reader = get_trace_reader(trace_file)
        self.trace_reader.build()

        if self.debug_mode:
            self.debug_interval_cnt = 0
            self.debug()

        while not self.trace_reader.end_of_trace(
        ) or not self.event_queue.empty():
            # Populate event queue if it is below the threshold number of events
            if self.event_queue.size() < Simulator.EVENT_QUEUE_THRESHOLD \
                    and not self.trace_reader.end_of_trace():
                self.populate_event_queue_from_trace()
                continue

            cur_event = self.event_queue.peek()
            trace_event = self.trace_reader.peek_event()
            if trace_event and cur_event.timestamp > trace_event.timestamp:
                self.populate_event_queue_from_trace()
                continue

            self.event_queue.pop()
            if self.verbose:
                print(cur_event)

            if self.debug_mode:
                self.debug_interval_cnt += 1
                if self.debug_interval_cnt == self.debug_interval:
                    self.debug()
                    self.debug_interval_cnt = 0

            self.broadcast(cur_event)
        self.finish()

    def populate_event_queue_from_trace(self):
        # Fill in event queue from trace
        events = self.trace_reader.get_events(
            count=Simulator.EVENT_QUEUE_THRESHOLD)
        [self.event_queue.push(x) for x in events]

    def finish(self):
        # Call finish for all modules
        for module in self.modules.values():
            module.finish()

    def subscribe(self, event_type, handler, event_filter=None):
        if event_type not in self.event_listeners:
            self.event_listeners[event_type] = []
        self.event_listeners[event_type].append((event_filter, handler))

    def broadcast(self, event):
        # Get the set of listeners for the given event type
        listeners = self.event_listeners[event.event_type]
        for (event_filter, handler) in listeners:
            # Send event to each subscribed listener
            if not event_filter or event_filter(event):
                handler(event)

    def register_alarm(self, alarm, handler):
        pass

    def debug(self):
        while True:
            command = input("(uamp-sim debug) $ ")
            if command:
                tokens = command.split(sep=' ')
                cmd = tokens[0]
                args = tokens[1:]
                if cmd == 'quit' or cmd == 'exit' or cmd == 'q':
                    # TODO(dmanatunga): Handle simulation quitting better
                    print("Terminating Simulation")
                    exit(1)
                elif cmd == 'interval':
                    if len(args) == 1:
                        try:
                            self.debug_interval = int(args[0])
                        except ValueError:
                            print(
                                "Command Usage Error: interval command expects one numerical value"
                            )
                    else:
                        print(
                            "Command Usage Error: interval command expects one numerical value"
                        )
                elif cmd == 'verbose':
                    if len(args) == 0:
                        self.verbose = True
                    elif len(args) == 1:
                        if args[0] == 'on':
                            self.verbose = True
                        elif args[0] == 'off':
                            self.verbose = False
                        else:
                            print(
                                "Command Usage Error: verbose command expects 'on' or 'off' for argument"
                            )

                    else:
                        print(
                            "Command Usage Error: verbose command expects at most one argument"
                        )
            else:
                break
Exemple #7
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def compute_path(grid,start,goal,cost,heuristic):
   
    # Use the OrderedSet for your closed list
    closed_set = OrderedSet()
    
    # Use thePriorityQueue for the open list
    open_set = PriorityQueue(order=min, f=lambda v: v.f)      

    # Keep track of the parent of each node. Since the car can take 4 distinct orientations, 
    # for each orientation we can store a 2D array indicating the grid cells. 
    # E.g. parent[0][2][3] will denote the parent when the car is at (2,3) facing up    
    parent = [[[' ' for row in range(len(grid[0]))] for col in range(len(grid))], 
             [[' ' for row in range(len(grid[0]))] for col in range(len(grid))],
             [[' ' for row in range(len(grid[0]))] for col in range(len(grid))],
             [[' ' for row in range(len(grid[0]))] for col in range(len(grid))]]

    # The path of the car
    path =[['-' for row in range(len(grid[0]))] for col in range(len(grid))]
    dist =[]
    P =[]
    x = start[0]
    y = start[1]
    theta = start[2]
    h = heuristic[x][y]
    g = 0
    f = g+h
    open_set.put(start, Value(f=f,g=g))
    for i in range(0,6):
        for j in range(0,5):
            if grid[i][j] == 0:
                dist = 10000000
                x = P(i)
                y = P(j
        c dfd #cIm just)

                open_set.put([i][j], dist)
    open_set.insert(goal,0)

    while not open_set.empty():
        x,y = open_set.pop()


    # your code: implement A*

    # Initially you may want to ignore theta, that is, plan in 2D.
    # To do so, set actions=forward, cost = [1, 1, 1, 1], and action_name = ['U', 'L', 'R', 'D']
    # Similarly, set parent=[[' ' for row in range(len(grid[0]))] for col in range(len(grid))]

    return path, closed_set


if __name__ == "__main__":
    path,closed=compute_path(grid, init, goal, cost, heuristic)

    for i in range(len(path)):
        print(path[i])

    print("\nExpanded Nodes")    
    for node in closed:
        print(node)

"""
Exemple #8
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    def shortest_path_to_closest(self, start, end):
        class FakePlayer(object):
            pass

        def heuristic(p):
            x, y = p
            end_x, end_y = end
            return abs(end_x - x) + abs(end_y - y)

        frontier = PriorityQueue()
        frontier.push((start, 0, None), heuristic(start))
        visited = set()
        shortest_links = set()

        # Explore until no more
        while not frontier.empty():
            (point, cost, prev) = frontier.pop()
            if point not in visited:
                visited.add(point)
                shortest_links.add((point, cost, prev))

                # Create a fake player to move
                x, y = point
                fake_player = FakePlayer()
                fake_player.cards = []

                # Add all children
                for m in PlayerMovement.all_moves():
                    fake_player.x = x
                    fake_player.y = y
                    if PlayerMovement.move(m, self._board, fake_player):
                        new_pos = (fake_player.x, fake_player.y)
                        new_cost = cost + 1
                        frontier.push((new_pos, new_cost, point), new_cost + heuristic(new_pos))

        # Work out closest visited to target
        best_link = None
        best_heuristic = math.inf
        for link in shortest_links:
            point, _, _ = link
            h = heuristic(point)
            if h < best_heuristic:
                best_link = link
                best_heuristic = h

        # Find the reversed path
        final_target, _, prev = best_link
        target = final_target
        rev_path = [target]
        while prev is not None:
            def match_link(i):
                (t, _, p) = i
                return t == prev
            # Find the prev link
            prev_link = list(filter(match_link, list(shortest_links)))
            assert(len(prev_link) == 1)
            target, _, prev = prev_link[0]
            rev_path.append(target)

        # Convert the coord-path to a move path
        path = list(reversed(rev_path))[1:]
        coord_path = path
        last_x, last_y = start
        move_path = []
        while path != []:
            next_x, next_y = path[0]
            path = path[1:]
            if last_x + 1 == next_x:
                move_path.append(PlayerMovement.RIGHT)
            elif last_x - 1 == next_x:
                move_path.append(PlayerMovement.LEFT)
            elif last_y + 1 == next_y:
                move_path.append(PlayerMovement.DOWN)
            elif last_y - 1 == next_y:
                move_path.append(PlayerMovement.UP)
            last_x = next_x
            last_y = next_y

        #print("target: {}; coord_path: {}; move_path: {}".format(final_target, coord_path, move_path))
        return final_target, move_path # Closest End Coord, Path
    def search(self, vobj):
        """The Hybrid State A* search algorithm."""

        tic = time.clock()

        get_grid_id = self.graph.get_grid_id

        frontier = PriorityQueue()
        frontier.put(list(self.start), 0)
        came_from = {}
        cost_so_far = {}

        came_from[tuple(self.start)] = None
        cost_so_far[get_grid_id(self.start)] = 0

        dubins_path = False

        num_nodes = 0

        while not frontier.empty():
            current = frontier.get()

            if num_nodes % self.dubins_expansion_constant == 0:
                dpath,_ = dubins.path_sample(current, self.goal, self.turning_radius, self.step_size)
                if not self.map.is_occupied_discrete(dpath):
                    # Success. Dubins expansion possible.
                    self.path_found = True
                    dubins_path = True
                    break

            if np.linalg.norm(current[0:2] - self.goal[0:2]) < self.eps \
               and np.abs(current[2]-self.goal[2]) < np.pi/8:
                self.path_found = True
                break

            for next in self.graph.neighbors(current, vobj.model.est_r_max):
                new_cost = cost_so_far[get_grid_id(current)] + \
                           self.graph.cost(current, next)

                if get_grid_id(next) not in cost_so_far or new_cost < cost_so_far[get_grid_id(next)]:
                    cost_so_far[get_grid_id(next)] = new_cost
                    priority = new_cost + heuristic(self.goal, next)
                    frontier.put(list(next), priority)
                    came_from[tuple(next)] = current

            num_nodes += 1
        # Reconstruct path
        path = [current]
        while tuple(current) != tuple(self.start):
            current = came_from[tuple(current)]
            path.append(current)

        if dubins_path:
            path = np.array(path[::-1] + dpath)
        else:
            path = np.array(path[::-2])

        print("Hybrid A-star CPU time: %.3f. Nodes expanded: %d" % ( time.clock() - tic, num_nodes))
        #print(self.start)

        return np.copy(path)
Exemple #10
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class Simulator(SimulatorBase):
    EVENT_QUEUE_THRESHOLD = 100

    def __init__(self):
        self._sim_modules = {}
        self._module_type_map = defaultdict(deque)

        self._device_state = DeviceState()
        self._event_queue = PriorityQueue()

        self._current_time = None
        self._warmup_period = None

        self._event_listeners = defaultdict(deque)
        self._trace_reader = None
        self._trace_executed = False
        self._verbose = False
        self._debug_mode = False
        self._debug_interval = 1
        self._debug_interval_cnt = 0

    def has_module_instance(self, name):
        return name in self._sim_modules

    def get_module_instance(self, name):
        return self._sim_modules[name]

    def get_module_for_type(self, module_type):
        if module_type in self._module_type_map:
            return self._module_type_map[module_type.value][0]
        else:
            return None

    def register(self, sim_module, override=False):
        if not isinstance(sim_module, SimModule):
            raise TypeError("Expected SimModule object")

        if sim_module.get_name() in self._sim_modules:
            raise Exception("Module %s already exists" % sim_module.get_name())

        self._sim_modules[sim_module.get_name()] = sim_module

        if override:
            self._module_type_map[sim_module.get_type().value].appendleft(sim_module)
        else:
            self._module_type_map[sim_module.get_type().value].append(sim_module)

    def build(self, args):
        self._verbose = args.verbose
        self._debug_mode = args.debug

        # Instantiate necessary modules based on config files
        config = configparser.ConfigParser()
        config.read(args.sim_config)

        config['DEFAULT'] = {'modules': '', 'warmup_period': ''}

        if 'Simulator' not in config:
            raise Exception("Simulator section missing from config file")

        sim_settings = config['Simulator']

        # Identify the set of modules to include
        modules_str = sim_settings['modules']
        if modules_str:
            modules_list = modules_str.split(' ')
        else:
            modules_list = []

        self._warmup_period = \
            self.__parse_warmup_setting(sim_settings['warmup_period'])

        # Setup the trace file reader and initial simulator time
        self._trace_reader = get_trace_reader(args.trace)
        self._trace_reader.build()
        self._trace_executed = False
        self._current_time = self._trace_reader.get_start_time()

        for module_name in modules_list:
            module_settings = {}
            if module_name in config:
                module_settings = config[module_name]

            self.register(get_simulator_module(module_name, self, module_settings))

        # Build list of modules
        for sim_module in self._sim_modules.values():
            sim_module.build()

    def run(self):
        # Check if we need to enter debug mode immediately
        if self._debug_mode:
            self._debug_interval_cnt = 0
            self.__debug()

        # Add alarm event for the warmup period
        warmup_finish_alarm = SimAlarm(
            timestamp=self._trace_reader.get_start_time() + self._warmup_period,
            handler=self.__enable_stats_collection,
            name='Warmup Period Alarm')
        self._event_queue.push(warmup_finish_alarm,
                               (warmup_finish_alarm.timestamp, Priority.SIMULATOR))

        while not self._trace_reader.end_of_trace() \
                or not self._event_queue.empty():

            # Populate event queue if it is below the threshold number of events
            if self._event_queue.size() < Simulator.EVENT_QUEUE_THRESHOLD \
                    and not self._trace_reader.end_of_trace():
                self.__populate_event_queue_from_trace()
                continue

            # Look at next event to execute
            cur_event = self._event_queue.peek()

            # Look at next event from trace file
            trace_event = self._trace_reader.peek_event()

            # If trace event is supposed to occur before current
            # event, than we should populate event queue with more
            # events from the trace file
            if trace_event and cur_event.timestamp > trace_event.timestamp:
                self.__populate_event_queue_from_trace()
                continue

            self._event_queue.pop()

            # Set current time of simulator
            self._current_time = cur_event.timestamp
            if self._verbose:
                print(cur_event)

            if self._debug_mode:
                self._debug_interval_cnt += 1
                if self._debug_interval_cnt == self._debug_interval:
                    self.__debug()
                    self._debug_interval_cnt = 0

            self.__execute_event(cur_event)
        self.__finish()

    def subscribe(self, event_type, handler, event_filter=None):
        if event_type not in self._event_listeners:
            self._event_listeners[event_type] = []
        self._event_listeners[event_type].append((event_filter, handler))

    def broadcast(self, event):
        if event.timestamp:
            if event.timestamp != self._current_time:
                raise Exception("Broadcasting event with invalid timestamp.")
        else:
            event.timestamp = self._current_time

        # Get the set of listeners for the given event type
        listeners = self._event_listeners[event.event_type]
        for (event_filter, handler) in listeners:
            # Send event to each subscribed listener
            if not event_filter or event_filter(event):
                handler(event)

    def register_alarm(self, alarm):
        self._event_queue.push(alarm, (alarm.timestamp, Priority.ALARM))

    def get_current_time(self):
        return self._current_time

    def get_device_state(self):
        return self._device_state

    def __parse_warmup_setting(self, setting_value):
        if setting_value:
            if setting_value.endswith('h'):
                num_hours = int(setting_value[:-1])
                return datetime.timedelta(hours=num_hours)
            raise Exception("Invalid warmup period setting format")
        else:
            return datetime.timedelta()

    def __enable_stats_collection(self):
        for sim_module in self._sim_modules.values():
            sim_module.enable_stats_collection()

    def __disable_stats_collection(self):
        for sim_module in self._sim_modules.values():
            sim_module.disable_stats_collection()

    """
        Private method that handles execution of
        an event object.
    """
    def __execute_event(self, event):
        if event.event_type == EventType.SIM_DEBUG:
            self.__debug()
        elif event.event_type == EventType.SIM_ALARM:
            if not self._trace_executed:
                event.fire()
                if event.is_repeating():
                    self._event_queue.push(event, (event.timestamp, Priority.ALARM))
        elif event.event_type == EventType.TRACE_END:
            self._trace_executed = True
        else:
            self.broadcast(event)

    def __populate_event_queue_from_trace(self):
        # Fill in event queue from trace
        events = self._trace_reader.get_events(count=Simulator.EVENT_QUEUE_THRESHOLD)
        for x in events:
            self._event_queue.push(x, (x.timestamp, Priority.TRACE))

    def __finish(self):
        output_file = sys.stdout
        # Print status from all modules
        for sim_module in self._sim_modules.values():
            header = "======== %s Stats ========\n" % sim_module.get_name()
            footer = "=" * (len(header) - 1) + '\n'
            output_file.write(header)
            sim_module.print_stats(output_file)
            output_file.write(footer)

        # Call finish for all modules
        for sim_module in self._sim_modules.values():
            sim_module.finish()

    def __debug(self):
        while True:
            command = input("(uamp-sim debug) $ ")
            if command:
                tokens = command.split(sep=' ')
                cmd = tokens[0]
                args = tokens[1:]
                if cmd == 'quit' or cmd == 'exit' or cmd == 'q':
                    # TODO(dmanatunga): Handle simulation quitting better
                    print("Terminating Simulation")
                    exit(1)
                elif cmd == 'interval':
                    if len(args) == 1:
                        try:
                            self._debug_interval = int(args[0])
                        except ValueError:
                            print("Command Usage Error: interval command expects one numerical value")
                    else:
                        print("Command Usage Error: interval command expects one numerical value")
                elif cmd == 'verbose':
                    if len(args) == 0:
                        self._verbose = True
                    elif len(args) == 1:
                        if args[0] == 'on':
                            self._verbose = True
                        elif args[0] == 'off':
                            self._verbose = False
                        else:
                            print("Command Usage Error: verbose command expects 'on' or 'off' for argument")

                    else:
                        print("Command Usage Error: verbose command expects at most one argument")
            else:
                break
    def search(self, vobj):
        """The Hybrid State A* search algorithm."""

        tic = time.clock()

        get_grid_id = self.graph.get_grid_id

        frontier = PriorityQueue()
        frontier.put(list(self.start), 0)
        came_from = {}
        cost_so_far = {}

        came_from[tuple(self.start)] = None
        cost_so_far[get_grid_id(self.start)] = 0

        dubins_path = False

        num_nodes = 0

        while not frontier.empty():
            current = frontier.get()

            if num_nodes % self.dubins_expansion_constant == 0:
                dpath,_ = dubins.path_sample(current, self.goal, self.turning_radius, self.step_size)
                if not self.map.is_occupied_discrete(dpath):
                    # Success. Dubins expansion possible.
                    self.path_found = True
                    dubins_path = True
                    break

            if np.linalg.norm(current[0:2] - self.goal[0:2]) < self.eps \
               and np.abs(current[2]-self.goal[2]) < np.pi/8:
                self.path_found = True
                break

            for next in self.graph.neighbors(current, vobj.model.est_r_max):
                new_cost = cost_so_far[get_grid_id(current)] + \
                           self.graph.cost(current, next)

                if get_grid_id(next) not in cost_so_far or new_cost < cost_so_far[get_grid_id(next)]:
                    cost_so_far[get_grid_id(next)] = new_cost
                    priority = new_cost + heuristic(self.goal, next)
                    frontier.put(list(next), priority)
                    came_from[tuple(next)] = current

            num_nodes += 1
        # Reconstruct path
        path = [current]
        while tuple(current) != tuple(self.start):
            current = came_from[tuple(current)]
            path.append(current)

        if dubins_path:
            path = np.array(path[::-1] + dpath)
        else:
            path = np.array(path[::-2])

        print "Hybrid A-star CPU time: %.3f. Nodes expanded: %d" % ( time.clock() - tic, num_nodes)
        #print self.start

        return np.copy(path)
Exemple #12
0
import matplotlib.pyplot as plt

G = nx.karate_club_graph()
for edge in G.edges():
    G[edge[0]][edge[1]]['weight'] = random.randint(1, 10)

source = 2
goal = 3

ref_nodes = PriorityQueue()
ref_nodes.put(source, 0)
dist_so_far = {}
came_from = {}
dist_so_far[source] = 0

while not ref_nodes.empty():
    current = ref_nodes.get()

    if current == goal:
        break

    for next_node in G.neighbors(current):
        new_dist = dist_so_far[current] + G[current][next_node]['weight']
        if next_node not in dist_so_far or new_dist < dist_so_far[next_node]:
            dist_so_far[next_node] = new_dist
            ref_nodes.put(next_node, new_dist)
            came_from[next_node] = current

print(came_from)
print(dist_so_far)