我正在构建一个机器人导航系统。 我正在使用AStar从起始单元到目标单元。 我有实现A STAR的这段代码。 问题是我需要我的A星具有（x，y）方向而不是 （行，列）方向。 我试图一遍又一遍地编辑代码，但一直得到奇怪的结果。 例如，尝试将表示单元方向的0和1切换为“跳”，例如从1,3到2,2的步骤“跳跃”，这是非法的。 希望得到一些帮助。
# Credit for this: Nicholas Swift
from warnings import warn
class Node:
"""
A node class for A* Pathfinding
"""
def __init__(self, parent=None, position=None):
self.parent = parent
self.position = position
self.g = 0
self.h = 0
self.f = 0
def __eq__(self, other):
return self.position == other.position
def return_path(current_node):
path = []
current = current_node
while current is not None:
path.append(current.position)
current = current.parent
return path[::-1] # Return reversed path
def astar(maze, start, end, allow_diagonal_movement = False):
"""
Returns a list of tuples as a path from the given start to the given end in the given maze
:param maze:
:param start:
:param end:
:return:
"""
# Create start and end node
start_node = Node(None, start)
start_node.g = start_node.h = start_node.f = 0
end_node = Node(None, end)
end_node.g = end_node.h = end_node.f = 0
# Initialize both open and closed list
open_list = []
closed_list = []
# Add the start node
open_list.append(start_node)
# Adding a stop condition
outer_iterations = 0
max_iterations = (len(maze) // 2) ** 2
# what squares do we search
adjacent_squares = ((0, -1), (0, 1), (-1, 0), (1, 0),)
if allow_diagonal_movement:
adjacent_squares = ((0, -1), (0, 1), (-1, 0), (1, 0), (-1, -1), (-1, 1), (1, -1), (1, 1),)
# Loop until you find the end
while len(open_list) > 0:
outer_iterations += 1
# Get the current node
current_node = open_list[0]
current_index = 0
for index, item in enumerate(open_list):
if item.f < current_node.f:
current_node = item
current_index = index
if outer_iterations > max_iterations:
# if we hit this point return the path such as it is
# it will not contain the destination
warn("giving up on pathfinding too many iterations")
return return_path(current_node)
# Pop current off open list, add to closed list
open_list.pop(current_index)
closed_list.append(current_node)
# Found the goal
if current_node == end_node:
return return_path(current_node)
# Generate children
children = []
for new_position in adjacent_squares: # Adjacent squares
# Get node position
node_position = (current_node.position[0] + new_position[0], current_node.position[1] + new_position[1])
# Make sure within range
if node_position[0] > (len(maze) - 1) or node_position[0] < 0 or node_position[1] > (len(maze[len(maze)-1]) -1) or node_position[1] < 0:
continue
# Make sure walkable terrain
if maze[node_position[0]][node_position[1]] != 0:
continue
# Create new node
new_node = Node(current_node, node_position)
# Append
children.append(new_node)
# Loop through children
for child in children:
# Child is on the closed list
if len([closed_child for closed_child in closed_list if closed_child == child]) > 0:
continue
# Create the f, g, and h values
child.g = current_node.g + 1
child.h = ((child.position[0] - end_node.position[0]) ** 2) + ((child.position[1] - end_node.position[1]) ** 2)
child.f = child.g + child.h
# Child is already in the open list
if len([open_node for open_node in open_list if child == open_node and child.g > open_node.g]) > 0:
continue
# Add the child to the open list
open_list.append(child)
def example():
maze = [[0, 1, 0, 0, 1, 0, 0, 0, 0, 0],
[0, 1, 0, 0, 1, 0, 0, 0, 0, 0],
[0, 1, 0, 0, 1, 0, 0, 0, 0, 0],
[0, 1, 0, 0, 1, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 1, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 1, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 1, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 1, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]]
start = (0, 0)
end = (7, 6)
path = astar(maze, start, end)
print(path)
if __name__ == '__main__':
example()